only on al jazeera america. >> iraqi soldiers and shia militias take back the city of tikrit. >> this is al jazeera live from london. also coming up, the head of nato say that russia is still arming rebels in ukraine as the u.s. announce new sanctions. seven months after the death that shook america, ferguson's police chief steps down amid allegations of racial bias. [music] >> copyright ruling against robin thicke and pharrell williams that could change the

music industry. >> hello, iraqi government forces and shia militia are advancing into the city of tikrit. their aim is to recapture the city from the islamic state in iraq and the levant, which has held it since last june. iraqi forces are said to move from the north where they're in control of a military hospital. also pushing towards the center of the city. the video shows troops and militiamen along side heavy vehicles in the neighborhood, recapturing tikrit giving a supply link against isil in the major northern city of mosul. >> this is northeastern tikrit iraqi army and sunni tribesmen are trying to push isil out of the city. >> we want to tell the iraqi people that tikrit will be

liberated and retaken from isil troops. we will liberate tikrit from isil. and from there we'll move to mosul. >> they shot footage on wednesday. tikrit is controlled by isil. the city is on the highway linking baghdad to mosul further north. progress has bid slow here. partly because of boobie traps left by isil and there is a threat to sniper fire. the iraqi army is confident that they will take tikrit. >> despite the injury to leave the battle i told them i would not leave. hopefully we'll take the city today. so far we're in control and we have the upper hand with no casualty as of yet. just like injuries. >> but there are fears if tikrit

falls, shia militias will take revenge on the sunni population for being seen as collaborators and sympathizers of isil. they have carried out revenge killings in the highly sectarian conflict. the iranian backed militias fighting along side shia militia number around 20,000 and there are 2,000 sunni tribesmen fighting along side them. the question is whether they'll be able to keep the peace after doing so. >> in a conference in northern iraq some sunni politicians have criticized iranian involvement in iraq saying they're worried about the role that shia militia are playing in iraq. >> and there are a number of external factors that will determine iraq's future. above all iran is waging it's own war. it is in more control of the

military operations than the united states. >> our response to the offensive in tikrit, a launch of suicide-bomb attacks in ramadi. five people were killed in the attacks including two police officers. one of the bombs exploded near a bridge in the western part of the city. >> and kurdish forces say isil fighters have taken part control of a village part of a large push to seize it. in the u.s. senate committee hearing whether to authorize formal actions against iran. our white house correspondent has the details. >> on the defensive after

sending an open letter to iran's leaders, in an taste to kill negotiations over the program. >> this letter is nothing more than topping iran from getting a newell bomb. if the headlines are an indication, it backfired big time. democrats and some republicans say it was out of line for 47 republicans to warn iran that the next president can throw out the deal or congress could change it. the u.s. secretary of state john kerry said it's also not true. >> it's incorrect when it says that congress can actually modify the terms of the agreement at any time. that's flat wrong. they don't have the right to modify an agreement reached executive to executive between leaders of a country. >> secretary kerry will travel sunday to continue negotiations. they say they don't think that the letter will impact the talks. >> the iranians given this letter will have an easier time saying we conceded all along.

you didn't have your house in order. but this letter, in the event there is no agreement by this summer makes the probability that the sanction regime will stay intact all much harder. it's hard to see that they're going to stick to. obama but the hard liners of the republican party. >> it makes it more likely if the negotiators strike a deal will stick no matter what republican leaders say or write about. patty colhane washington. >> the police chief in the u.s. city of ferguson has resigned after aous department investigation found evidence of racially biased practices in the force. tom jackson has been under pressure since an officer shot dead an unarmed black teenager

last year. tell us more about this report and why this resignation has happened. >> well, it was an amazing report. you don't see this very often i suppose. the details in the report were pretty appalling. the local police force in ferguson saw the local black population, and it's a very poor community of a means of raising millions of dollars from municipal coffers. they saw what they did was they targeted, they arrested, they jailed, then kept members of the africa community in jail. and each day they're in jail their fines would go ever higher. all of this to simply make money. now this police chief said there is nothing untoward. there was no racism in this city. and, in fact, the resignation has been called a mutual separation by local authorities. that is a long way away from him

being fired and held to account. many of the protesters have been long demanding. we are expecting a press conference, and we're expecting a press conference. we're now getting reports that he's telling journalists that he's out of town. we won't necessarily hear from him. >> in the events there have turned into something which is an national significance haven't they? >> it has and it has to be remembered that there is just one element of what demonstrators both in ferguson and around the country have been demanding. in ferguson there have been reports from demonstrators saying this is welcomed, but it's not enough. first of all there, is a certain amount of disappointment that the police chief is not being held to account but back to what the demonstrators are calling for is a dissolution of the entire local police force. they say the entire thing is rotten that's something that the attorney general eric holder did not rule out on friday.

they want more investigations around the county. they said ferguson is not the only place doing this, preying on the african-american community for money they're doing it elsewhere. and the mayor has been charged he's presided nominally over this, he said he knew nothing about it because his position is part time. and then there is the nationwide element. this is about black lives mattering, and a country in which you're young black male, you're 21 times more likely to be shot dead by an officer than if you're a young white male. and it's beyond that, there are other issues. >> thank you very much, indeed. venezuela's parliament has approved a bill that would give the president more powers. nicholas maduro walked into carrying the bill tellling members that it was needed to

help fight american imperialism. the correspondent virginia lopez has more from caracas. >> last night president maduro began the address the nation what has started as a peaceful message took on a fiery note, and ended with maduro not only accusing obama of being the next nixon but requesting the national assembly to grant him special powers so they could confront whatever imperialist actions they may impose on venezuela. you know, clearly despite some call for reflection or peaceful measures or commitment from

maduro to handle this in a peaceful manner, the aggressive tone and anti-american rhetoric continues. >> the president announcing a one one-month halt on airstrikes on rebel camps. >> another step towards peace, but not an end to hostilities at least not yet. >> to help de-escalate the conflict, i've decided to cease pom bombardments of farc camps for one month. >> they cited the cease-fire for the reasons to halt attacks on the camps. >> they will continue fighting

against extortion, kidnappings and drug trafficking. there is no confining of the armed forces, no retreats. >> however temporary and incomplete this decision is the most important step yet to end hostilities in this 50-year-old conflict, about the but not everyone is happy many worry that the government is giving up its most successful weapon in the fight against the rebels. since 2008 three 2008 three members of the farc have been killed. they say they fear the president is making too many concessions that is putting colombians at risk. >> we see our government kneeling in front of the farc. they will cry a literal cease-fire and this is what they will get. they will not spend a day in prison, and the president has

not said a word about that either. >> a political analyst agreed this is a response to a situation that has already changed on the ground. >> it materializes and formalizes the large reduction of violence that we've seen, that farc has been complying with self-imposed cease-fire. now, it is becoming bilateral these will, indeed, further reduce the levels of violence. >> peace negotiators will travel back to havana march 17th, to continue discussing the thorny issue of transitional justice. this time there is some hope that could push the talks towards a final resolution. al jazeera bogota. >> still to come, another bump in the road for the high profile of sometimes controversial tv

host jeremy clarkson. >> in ukraine they're running out of drugs to get addicts off heroin.

>> a reminder of the top stories here on al jazeera. iraqi government forces receive support from militiamen. tikrit has been held by isil fighters since june. secretary of state john kerry has strongly criticized republican senators after writing an open letter to iran warning of any nuclear deal

reached with the u.s. could be thrown out by the next president. the department of justice found racially biased actions in ferguson. nato has accused russia of continuing to arm separatist fighters in ukraine's east. they called on russian to russia to leave the territory in agreement with the minsk agreement. >> we've seen a strong support for separatists in eastern ukraine. we see the delivery of equipment forces training, so russia is

still in eastern ukraine. they have over a long period the substantial support for the separatists. >> they are accused of causing conflict in eastern ukraine. penalties have been placed on a russian bank and the u.s. will deliver humvees and drones to ukraine. reports of drug use on the rise. and the sharing of needles has led to the increase of hiv infections. ukraine is already the worst infected of hiv in europe. 150,000 people ages 15 to 49 are infected.

john hedron reports from donetsk. >> it's a nearly daily ritual. every morning but sunday bruce will make the rounds distributing needles, antibacterial wipes and con domescondoms. donetsk is running out of the drugs that they use to help get people off heroin. >> they reduced doses so quickly that i've had a fever for the past month. even if we can find it we can't afford it. we have no money. there is war. >> ukraine's government has long supplied the drugs for heroin substitution therapy but in separatist territory that up a stopped. they use two drugs in heroin treatment, and as substitutions

run out heroin use rises and since heroin users tend to share needles, so will hiv. >> we have less medicine, and we have to reduce doses to make it last longer. patients have to live on minimal doses. some have left the programs to live without substitution therapy. >> already 300 patients in the separatist cities of donetsk and luhansk has lost access to methadone. >> h.i.v. has increased because many people shoot up as well as taking the methadone because the methadone dose is small. many people on substitution therapy started families, got jobs and no longer abuse drugs. >> but a few have gone cold turkey, and horse have returned to use.

john hedron. >> algeria's said it has only one town left to attack from boko haram. there have been pledge more troops to help against boko haram. it would provide indirect support. jacky rowland reports. >> french soldiers on patrol in the streets of mali one example of how the french military is heavily engaged in its former colonies in africa. right now 8,000 french troops are deployed in foreign peacekeeping missions, which is straining the armed forces to the limit. >> one of the solutions to say that we're not the only country to have this goal to fight

against this, more and more we ask for help from the european union to pay more, to do more for military operations abroad. >> on top of the overseas missions another 10,000 troops are currently deployed inside france itself. this is in direct response to the attacks in paris in january in which 17 people were killed. more demands are being made on the military than were budgeted for. this is a time of economic crisis in france. all government departments under pressure to reduce public spending so that the defense ministry has had to make a special case as to why it should be an exception. >> maintaining an army that is fighting fit is an expensive business. while some units are on active duty others are training back at base. then there is the equipment, the

army says it must have the most up-to-date technology to confront current and potential enemies. >> we have around 30,000 people deployed out of 70,000. that's almost one out of two. that's too much. and currently if we maintain the deployment, we have to increase our training. >> france remains on its highest state of alert. the president wants to keep the current number of troops on the streets particularly outside of synagogues and jewish schools. this military presence will be part of french life for some time to come. jackie rowland paris. >> demonstrating against an u.n.-brokered peace plan. it has been signed by the government but not yet accepted by the tuarig groups.

pharrell williams and robin thicke has been ordered to pay robin marvin gaye's family $7 million for copyright violations of his music. they've been told they have to give it up. [music] >> williams and thicke plan to rule against the appealing meanwhile the gaye family will seek an injunction against the track. >> i feel free--free from--honestly free from pharrell williams and robin thicke's chains, and they tried to keep on us, and the lies that

were told, and the fact that we were able to break through any way. >> his tv motoring show has brought him fame and welt around the world. now his career hangs in the balance after allegedly hitting a producer. >> jeremy clarkson is one of the biggest names on television, his motoring show, he's suspended for reportedly punching his producer puts the program's future and his own in question. for the top gear brand specifically it will have a detrimental effect. it's hard to see that they would be able to replicate the show in its current form without him. they could maybe relaunch it, but it wouldn't be quite the same show, and it's hard to imagine it would have the same popularity. >> clarks son was given a final

warning by the bbc after his use of a racial slur. it proffered a prompted an apology on twitter. >> it's a word i loathe. >> also in 2014 clarkson caused riots in argentina after filming in this porch with a plate porsche with a numbers plate thought to refer to the 19th 82 falklands' war. he has offended, romanians albanians, germans, barks bbc. why has he continued? he hosts one of the top shows

with 350 million viewers and jeremy clarkson has a mega following. within 24 hours of the news of the incident, hundreds of thousands of fans had signed an online petition demanding his reinstatement. the bbc only say that clarkson has been suspended pending an investigation during a fraca with a producer. that means this, the show's most recent episode could turn out to be it's last. >> now returning to america's got talent, not for singing but for science. the science search in washington, a highly coveted award with many of its winners going on to become winnow bell prizeswin nobel prizes.

>> the judges pick just 40 students for the final round. jesse's project to find out what triggers the cold weather phenomenon called polar vortex. >> the more you learn, the more connected everything is, it seems i've always been drawn to topics like this. >> another focusing on the maneuver called the flick. >> i wanted to take a scientific approach and see if they were right. >> her conclusion coaches were wrong. and. >> nuclear power and clean energy super connecting wires are wires with no resistence which would make electricity half as expensive. that's where things like that come from. >> fame aside there is quite a bit of fortune for the three top winners this year.

each teenager collecting $150,000 prize. >> michael won for innovation, both amazing and delighting his parents. >> oh, my god you won. >> eight nobel prize winners have been finalists in this 73-year-old competition. one laureate said that science these stays has been falling short on two counts. one is high risk-high reward research, and the second is the risk risk for young people. both must be supported at national and international levels. >> at this gala comes recognition that what they do really matters. tom ackerman, al jazeera, washington. >> nasa has tested the largest most powerful engines ever built decide designed to reach to the moon and beyond.

scientists are hoping to be able to explore further than ever before. go to our website www.aljazeera.com and you can watch us live by clicking on the "watch live" i con icon, once again, www.aljazeera.com. . >> again, we're standing by, we'll be back with that news conference begins.