and by bnsf railway. and the william and flora hewlett foundation, working to solve social and environmental problems at home and around the world. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> ifill: japan suffered two major blows today, as a desperate effort continued to head off a nuclear crisis on the heels of a catastrophic earthquake and tsunami. a new explosion rocked a shut- down reactor at a plant that lost its cooling system in friday's disaster. and the u.n. nuclear agency warned a second reactor was failing as well. thousands of people had already been ordered out of a 12-mile exclusion zone around the plant. today, another 140,000 people living 12 to 20 miles away were told to stay indoors, and officials imposed a no-fly zone around the site. we have a series of reports from independent television news, beginning

. >> and by bnsf railway. pacific life. >> and by the bill and melinda gates foundation. dedicated to the idea that all people deserve the chance to live a healthy productive life. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> brown: japanese engineers marshaled all their remaining tools today in the week-long struggle to prevent a full-blown nuclear disaster. and in washington, president obama sought to reassure americans about the potential for radiation to drift over the u.s. >> we do not expect harmful levels of radiation to reach the west coast, hawaii, alaska, or u.s. territories in the the pacific. that is the judgment of our nuclear regulatory commission and many other experts. furthermore, the centers for disease control and prevention and public health experts do not recommend that people in the united states take precautionary measures beyond staying informed. >> brown: the presiden

bnsf railway. and the william and flora hewlett foundation, working to solve social and environmental problems at home and around the world. and with the ongoing support of these institutions and foundations. this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> brown: libyan forces stepped up their counter-offensive against opposition fighters today. a barrage of firepower assaulted rebels on fronts to the east and west of the capital. we have two reports from independent television news correspondents in libya. we begin with lindsey hilsum. she's in the oil port of ras lanouf, about 400 miles east of tripoli. >> reporter: heading for the front line. with the blessing of their comrades still determined to drive out colonel qaddafi forces, this is the last rebel check point before no man's land. the rebels are making forays into that area and skirmishing further ahead. they don't seem to be making muc

. >> and by bnsf railway. >> and by the bill and melinda gates foundation. dedicated to the idea that all people deserve the chance to live a healthy, productive life. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> woodruff: libyan warplanes carried out repeated air strikes today, and fears of a rising humanitarian crisis grew. we have two reports from independent television news, starting with bill neely in misrata, a western town surrounded by forces loyal to libyan leader moammar qaddafi. >> reporter: colonel qaddafi's got a grip on western libya, but not here. and the town of misrata rebels fight street battles with his men. it's urban, intense and deadly. the rebels say dozens of have been killed. this one of qaddafi's tanks. his men fought their way in but were beaten back. the rebels celebrating, but they haven't won yet. qaddafi still sits confidently in power. here denoun

. >> and by bnsf railway. >> and by bnsf railway. >> and by the bill and melinda gates foundation. dedicated to the idea that all people deserve the chance to live a healthy, productive life. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> woodruff: world powers moved today to tighten the screws on libyan leader moammar qaddafi. as they did, new protests broke out in and around tripoli, and security forces rushed in to disperse them. but qaddafi, in an interview with abc news, refused to acknowledge there were any protests in tripoli. >> they left me all. they will die to protect me. >> woodruff: we begin with a report from jonathan rugman of independent television news, who's in tripoli. >> reporter: in a suburb of libya's capital an extraordinary act of defiance. the leader of the last 41 years is torn to shred ares and trampled underfoot. and then the flag of colonel khadaffi's revolution is set alight

bnsf railway. and the william and flora hewlett foundation, working to solve social and environmental problems at home and around the world. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> ifill: the rebel drive across northern libya turned into a panicked pullback today. moammar qaddafi's forces laid down a barrage of heavy weapons fire on the approaches to sirte, qaddafi's home town. the outgunned rebels were forced to flee the way they'd come. we have a report from lindsey hilsum of independent television news at the front lines. >> reporter: the rebels were gathering when the bad news started to come back down the road. just after dawn, those approaching sirte had been attacked by armed civilians loyal to colonel qaddafi. >> they started to shoot at us from houses and trees. it was an ambush. they were qaddafi's and m

pacific life and by bnsf railway. and the william and flora hewlett foundation, working to solve social and environmental problems at home and around the world. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> woodruff: more and more refugees crowded libya's borders with tunisia and egypt today. the u.n. estimated that 140,000 people-- most of them foreigners-- have fled the violence inside libya. and tunisian guards at a main crossing point fired into the air at times today, as they strained to maintain order. we have a report on the tunisian border from alex thomson of independent television news. >> reporter: desperate to get into tunisia and for some the wait is too much. manhandled over the frontier walls into the hands of the medics. on the wall they kick them, they hit them, but still plenty get through. which tunisia is allowing but o

. >> and by bnsf railway. >> and by the bill and melinda gates foundation. dedicated to the idea that all people deserve the chance to live a healthy, productive life. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> lehrer: a coalition led by the u.s. military hit libya today with a dozen more cruise missiles. it was the latest wave of attacks that began saturday night. the goal was to impose a no-fly zone and stop moammar qaddafi's forces from attacking civilians. in chile, president obama said the coalition acted to uphold a core principle. >> when the entire international community almost unanimously says that there is a potential humanitarian crisis about to take place, that a leader who has lost his legitimacy decides to turn his military on his own people, that we can't simply stand by with empty words. >> ifill: the president said the u.s. would turn over leadership of the o

bnsf railway. pacific life-- the power to help you succeed. and by toyota. and by the alfred p. sloan foundation. supporting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. aptiing sponsored by acnl/lehrer proctns captioned by media access group at wgbh access.wgbh.org

and by bnsf railway. and by the bill and melinda gates foundation. dedicated to the idea that all people deserve the chance to live a healthy, productive life. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> ifill: the libyan rebels' drive to oust moammar qaddafi reached the outskirts of his hometown and tribal base today. fighting erupted outside the city of sirte, home to 100,000 people. it's a key stronghold guarding the approaches to tripoli, 225 miles away. the rebels had already rolled up a series of eastern cities in a lightning advance over the weekend, behind a curtain of coalition air strikes. we have a report from outside sirte from lindsey hilsum of independent television news. >> reporter: they're fighting just east of sirte, colonel qaddafi's birth place. the rebels who swept up the road yesterday found his tanks waiting for them today. rumors have spread that

and by bnsf railway. and by the bill and melinda gates foundation. dedicated to the idea that all people deserve the chance to live a healthy, productive life. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> ifill: thousands of bodies of earthquake and tsunami victims washed up today in northeastern japan. the confirmed death toll was near 1,900, but there were estimates of more than 10,000 dead in the miyagi region, hardest hit by the catastrophe. meanwhile, survivors struggled to find food, water, and shelter as engineers labored to prevent a nuclear disaster. four days into the disaster and the devastation is almost beyond words. and spreads as far as the eye can see. whole towns, gone. in their place, mounds of wreckage. today new images emerged capturing the moment friday's tsunami ripped through a residential area. the amateur video was taken by people who ran to high

. >> and by bnsf railway. and by the alfred p. sloan foundation.rting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. captioning sponsored by macneil/lehrer productions captioned by media access group at wgbh access.wgbh.org vo:geico, committed to providing service to its auto insurance customers for over 70 years. more information on auto insurance at geico.com or 1-800-947-auto any time of the day or night.

. >> and by bnsf railway. and by the alfred p. sloan foundation.rting science, technology, and improved economic performance and financial literacy in the 21st century. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. captioning sponsored by macneil/lehrer productions captioned by media access group at wgbh access.wgbh.org "the electric company" is brought to you by... find your voice and share it, american greetings, proud sponsor of "the electric company." agreement from the u.s. department of education's ready to learn grant, and viewers like you, thank you. ve words: beatbox -- when you beatbox, you keep a beat with sounds from your mouth. tempo -- tempo is how fast or slow music is played, the beat. double time -- when you take a beat and do it twice as fast, that's double time. triple time -- three times as fast is triple time.

and by bnsf railway. and the william and flora hewlett foundation, working to solve social and environmental problems at home and around the world. and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> brown: moammar qaddafi showed no sign of backing down today, even as u.s. and british submarines fired another 20 cruise missiles at targets in libya. he appeared for the first time since the coalition attacks began on saturday. earlier tanks and troops local to qaddafi blasted a town near the tunisian border and the city of misrata east of tripoli. the u.s. task force commander, admiral samuel locklear, said the coalition was "considering all options" on how to respond. we have a series of reports from independent television news, beginning with john ray in tripoli. >> reporter: coalition air strikes are hitting home. the evidence show