it was just horrifying. just three months after the disappearance, the government announced they had solved the case. we were analysing the evidence. it was just not matching the official story. protests erupted across mexico. a team of independent experts began their own investigation and the government case starts to unravel.

the mexican government claimed the students were on four buses when they were attacked. but cctv revealed students on a fifth bus.

we saw that the mexican government was officially stating that the guerreros unidos were simply a local gang, and we knew that not to be the truth at all. my name is mark guiffre, and for 30 years, i was a special agent with the us drug enforcement administration. prior to the disappearance of the students, we had received intelligence that there was going to be activity relating to the movement of illicit heroin proceeds coming out of this particular location. we got authorisation to conduct

a search of that location. and there we seized many kilograms of heroin, money counters, a quarter of a million dollars or so in cash and illicit heroin trafficking records. we knew that day that we had cracked into a major criminal organisation with direct ties to iguala, guerrero. we received orders from a us district courtjudge and we began to conduct intercepts. we initiated surveillance operations, and in a very short period of time, we were able to determine that they were using passenger buses to smuggle large amounts of heroin — in hidden compartments — going back and forth between the chicago area and guerrero, mexico. based on the intelligence, we could easily determine that this organisation,

conservatively, was smuggling 200kg a month to chicago, which is over 2,000 kilograms a year, which is an absolutely unprecedented amount of heroin coming in to the united states by a single organisation. that's well over $122 million in a year. it was mind—boggling. what mexican authorities were saying was that nobody knows for sure why the students were attacked and disappeared. we knew that buses were being used by the guerreros unidos cartel. and we knew that the students were on buses. it seemed to us that it was clear as could be that the students unknowingly hijacked the wrong bus. four years on, the remains

ofjust one student have been found.

four years on, the remains ofjust one student have been found. there have been a handful of arrests, but no convictions. and the parents are still searching for their missing sons. viva mexico!

in 2018, there's a presidential election. andres manuel lopez 0brador was an outsider, a political outsider. he has mass popular support, but the political elite hate him. he won that election with an overwhelming mandate.

he made one explicit campaign promise to address an issue of human rights, and that was the forced disappearance of the 43 students. and he did that when he was on a campaign stop in iguala. he explicitly said, "i will find the 43 students "and i will bring the people who did it to justice." and the families believed it.

when lopez 0brador took power, he issued a decree to set up a truth commission.

also, the decree set up a special prosecutor's office. they named the special prosecutor, 0mar gomez trejo. 0mar gomez trejo was someone with a serious human rights background, a mexican man. he had worked for the independent experts group, the giei. this is somebody who can and will actually investigate.

the previous administration's case had rested on the confessions of cartel suspects.

0mar gomez and his team obtain and verify more than 60 interrogation videos.

by march 2020, there is enough evidence to indict tomas zeron. he once led the federal investigation into the missing 43. he is now wanted for his alleged role in a cover—up.

the mexican government requests an international arrest warrant through interpol. but mexico doesn't have an extradition treaty with israel.

in the final months of 2019, after discovering the use of torture in the original investigation, key suspects are released from prison and agree to be reinterviewed by 0mar. the work was for weeks and even maybe some months and, you know, really searching

a very large area. and. . .that�*s where the remains were found. we did the laboratory analysis, the anthropological examination the work was for weeks and even maybe some months and, you know, really searching a very large area. and. . .that�*s where the remains were found. we did the laboratory analysis, the anthropological examination of the remains. and then we analysed the results that came out from the processing of those remains and the identifications that it produced of two more students. the two identifications —

one belonged tthosivani guerrero de la cruz and the other one matched the family of christian rodriguez telumbre.

when the special prosecutor's unit was getting really close to full documentation of the events that night, which included military participation, they dynamited the case.

hello, there. some very mild conditions around at the moment. plenty of cloud, but also some sunshine at times, such as here in aberdeenshire on friday. a blustery day of weather but temperatures lifted 15 degrees. 15.5 degrees in the south—east of northern ireland, but towards western coasts, a very different story. still mild, but grey, drizzly, lots of low cloud, mistand murk, and not a lot is set to change through the weekend. it certainly stays mild and it will be blustery, too, with brisk south—westerly winds blowing. on saturday, high pressure remains to the south, we keep the strength of the wind, this cold front just thinking a little further

southwards, but not making too many inroads at all into the south of england and wales, where, again, a very mild start on saturday morning. temperatures in double figures, clear spells through the night. further north, here a chillier start to the day but again temperatures well above the average, but it's across northern england, northern ireland, and eastern scotland where we see the best of the day's sunshine. still strong, gusty winds to the east of the pennines, showers piling into western scotland, and where we have this cold front across wales and stretching into east anglia, some outbreaks of rain on and off, but it is grey, drizzly, mild for the south of the front, 13 or 14 celsius. even in cardiff, temperatures all the way up to 11 degrees as we go through the afternoon, for the six nations rugby, there will be a brisk, westerly, south—westerly wind blowing, as well.

on sunday, a few changes. now, this is a warm front. it will be dragging that very mild air further northwards, as we head throughout the day, so we will see some rain to start the day in northern ireland, that rain pushing into western scotland, where it will turn really quite heavy, particularly as we go into the evening. again, very mild—feeling conditions, 8 to 14 celsius, those temperatures picking up in northern scotland late in the night. some particularly heavy downpours across western scotland as we head through sunday night and again into monday, some more spots, across western ross, into argyll, could see as much as 150 to 170 millimetres of rainfall. elsewhere, across the rest of the uk on monday, largely dry, again, if you are spots of dried to the west, the rest of the brightness will be towards the east but temperatures once again for many 12 to 14 celsius. there will be some brightness around on monday. on tuesday, we start to see perhaps a little bit more in the way of rain, and a northerly wind developing could bring us colder conditions into wednesday.

live from washington, this is bbc news. the us carries out retaliatory air strikes against dozens of targets in syria and iraq, linked to iran. this comes in response to send a's attack injordan that killed three us service members. president biden says the us response will continue at times and at places of its choosing. hello, i'm caitriona perry. you're very welcome. the us has carried out retaliatory air strikes against iranian backed targets in iraq and syria, hitting 85 positions

in total. the white house as aircraft struck three targets in iraq and four in syria. these are new pictures released by us central command of b one bombers taking off to carry out the air strikes. president biden has issued a statement, saying... the strikes are in retaliation for the drone attack on sunday that killed three us soldiers and injured dozens more. iran denies involvement, calling the accusations are baseless, and saying it was not involved in the decision—making of resistance groups. now, the us said it did inform the iraqi

government about the strikes