Transcript for This day in history: Dec. 27, 2007

Pakistan may be the world's most dangerous country. Tonight is on the edge of chaos after the assassination of its most popular leader. Former prime minister Benazir Bhutto. Who electrified her country when she returned from exile and took on Pakistan's ruling party was struck down today by bullets on a bomb. Days away from an election she was poised to win. Her killing has sparked riots across Pakistan it also poses a serious challenge to America's security. We begin tonight when ABC's Gretchen Peters in Islamabad. Tonight George Pakistan is a nation in shot there is an incredible range of emotion here from greet her rage. Most of all there is here or Pakistan's increasingly uncertain future. Bhutto had just finished addressing thousands of supporters at a political rally. As her armored car inched out of the park she stood up to a sunroof to wave goodbye. Suddenly three shots rang out seconds later a massive explosion. Photographer John Moore was just yards away. I heard if you gunshots. Been as if she fell down into the vehicle and quickly thereafter there was bomb blast and bodies and pieces of car. Things were flying through the year of the stampede. The smell of burnt flesh it's terrible. Doctors tried desperately to revive her but it's 6:16 PM she succumbed to a bullet wound to Wear neck crowds that swarmed the hospital. And emerged to break the terrible news and I'm woman's. She has been martyred. I thought the main focus of their rage President Pervez Musharraf who do it. Allowing Pakistan to slide. Extremism that the that don't keep up Musharraf quickly condemned her killing. Legislative elections are to take place in twelve days to go ahead. Bhutto's party was favored to win those elections she had returned here in October after eight years in self imposed exile. To lead her Pakistan People's Party to victory. Didn't give what does that wasn't invented by Islamic terrorists but more than that it was presented by a box on security establishment and so. Get to bid up it. Bid off that one thing the founding. 50000 turned out to welcome her home but are homecoming parade was marred by a suicide bomber. You got killed almost 140 people Bhutto narrowly survived. Late tonight supporters carried a coffin from the hospital. As crowds surged forward to trying get a final glimpse of their fallen heroine. What she would not be able to keep getting her life she may be used to do that and habit. And humidity control of both with what democracy which can visit Greek island and port at this point of time. Tonight George amid fears of further violence tens of thousands of police and paramilitary troops are trying to lock down the country. Flights have been rounded buses and trains halted. Benazir Bhutto's body is being flown to the family estate in lark on where she is to be buried on Friday.

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