Pakistan is reeling from grief and angrily rioting after opposition leader Benazir Bhutto was killed today by an assassin who shot her twice and then blew himself up.
Bhutto's body, accompanied by her husband, Asif Ali Zardari, and their three children, was flown in a military aircraft to her home province of Sindh in the south of the country hours after she was killed.
People started crying and wailing as Bhutto's coffin was brought to her family home in an ambulance.
"Show patience. Give us courage to bear this loss," Zardari urged the mourners as the coffin was carried into the house.
Within minutes of the former prime minister's death, furious and heart broken supporters began breaking windows at the hospital where she died, burning campaign posters of President Pervez Musharraf and stoning police and passing cars.
Hours later, several banks, government offices and cars were burning in Hyderabad. Shop owners in Karachi locked their doors in protest and self-defense. A train was halted and set on fire along with government-run grocery stores and election offices. Car tires were set ablaze in cities across the country to block intersections in protests that raised fears the entire country could be engulfed in violence.
Musharraf appeared on national TV to blame terrorists for Bhutto's death and vowed to kill or capture her murderers. But he also urged the country to remain calm and put the country's paramilitary forces on "red alert" to contain the fury. A three-day mourning period was announced and schools and banks will also be closed.
FBI and Homeland Security officials sent a bulletin late Thursday to U.S. law enforcement agencies citing Islamist Web sites as saying al-Qaida had claimed responsibility for the attack and that the group's No. 2 leader, Ayman al-Zawahri, had planned it.
The bulletin, which was summarized by a law enforcement official who received it, cited no specific threats against the United States. The official asked to remain anonymous because he was not authorized to speak publicly about the bulletin.
In Pakistan, the unrest was fiercest in Bhutto's native Sindh province and its capital, Karachi, where two police officers were wounded.
"Police in Sindh have been put on red alert," said a senior police official. "We have increased deployment and are patrolling in all the towns and cities, as there is trouble almost everywhere."
Nawaz Sharif, another former prime minister and opposition leader, said his party would boycott next month's elections.
"I demand that Musharraf should quit immediately," Sharif added.
Pakistan's distress was displayed when her wooden coffin was taken from the hospital to an ambulance and thousands of Pakistanis surged around, trying to touch it. It was only with difficulty that they were able to push through the sea of people, the coffin riding overhead on the hands of dozens of jostled pallbearers as they struggled to reach the ambulance.
Bhutto was among at least 20 killed in the blast that left the park in the city of Rawalpindi a grisly scene of chaos, body parts and blood.
John Moore, a photographer and eyewitness to Bhutto's assassination, said, "I heard a few gunshots. Benazir -- she fell down under the vehicle and quickly there was a bomb blast. And bodies and pieces of car -- things were flying through the air. There was a stampede, the smell of burned flesh. It was terrible."
Bhutto was rushed to a nearby hospital while rescue workers hurried to put victims in ambulances as people wailed nearby. The clothing of some of the victims was shredded and people put party flags over their bodies. Police caps and shoes littered the asphalt.
In the confusion, it wasn't clear exactly what had happened, but Sardar Qamar Hayyat, a leader from Bhutto's party, said he was standing about 10 yard from Bhutto's vehicle.
"She was inside the vehicle and was coming out from the gate after addressing the rally when some of the youths started chanting slogans in her favor," he said. "Then I saw a thin, young man jumping to her vehicle from the back and opening fire. Moments later, I saw her speeding vehicle going away."
Party supporter Chaudry Mohammed Nazir said that two gunshots rang out when Bhutto's vehicle pulled into the main street and that there was a big blast next to her car.
A security adviser to Bhutto's party said she was shot in the neck and chest.
The gunman then blew himself up.
Initial reports said Bhutto, 54, was unharmed in the attack, but about an hour later her supporters' worst fears were confirmed.
Sen. Babar Awan, Bhutto's lawyer, said, "The surgeons confirmed that she has been martyred."
There was no immediate claim of responsibility for the killing, but at Rawalpindi General Hospital furious Bhutto supporters erupted in anger at Pakistan's president, Pervez Musharraf, chanting "Killer, Killer, Musharraf" and calling him a "liar."
The Pakistani military was in charge of security at the rally and it was the second time since Bhutto returned to Pakistan in October that an assassin slipped past security.
During her triumphant return to the country, Oct. 18, a suicide bomber blew himself up near Bhutto's vehicle, killing more than 140 people. Bhutto survived that attack.
"We repeatedly informed the government to provide her proper security and appropriate equipment including jammers, but they paid no heed to our requests," said Rehman Malik, Bhutto's security adviser.
Last month, Bhutto had also planned a rally in the city, but Musharraf forced her to cancel it, citing security fears.
Pakistan's Islamic militants have long had Bhutto under a death sentence for her opposition to their fundamentalist ambitions. There were also tensions between Bhutto and Musharraf after negotiations to share power had stalled.
In his televised address to the nation, Musharraf blamed his rival's death on terrorists and vowed, "we will not rest until we eliminate these terrorists and root them out."
But Sharif, another former premier who was deposed by Musharraf, rushed to the hospital where Bhutto had died and in an address to the crowd suggested the Musharraf government was at fault.
"Benazir Bhutto was also my sister, and I will be with you to take the revenge for her death," Sharif said. "Don't feel alone. I am with you. We will take the revenge on the rulers."
Today's attack took place as Bhutto was leaving a political rally where she addressed thousands before the country's Jan. 8 parliamentary elections.
The killing has staggered Pakistan. Musharraf had put Pakistan under emergency rule last month and postponed elections. Under pressure from the White House, Musharraf rescheduled the elections for January and lifted emergency rule.
It remains to be seen whether the elections will proceed on schedule and Musharraf has convened an emergency meeting with his senior staff where they are expected to discuss whether to postpone the election, an official at the Interior Ministry said, speaking on condition of anonymity because of the sensitivity of the talks.
The political murder could also unsettle the Bush administration's agenda. Pakistan is the Bush administration's closest ally in the region for fighting terrorists, but Bhutto's death is likely to further destabilize an already volatile situation in Pakistan.
White House spokesman Scott Stanzel said President Bush, who was staying at his Crawford, Texas, ranch, was informed of Bhutto's death within minutes of the announcement in Karachi.
Bush later issued a statement, saying, "The United States strongly condemns this cowardly act by murderous extremists who are trying to undermine Pakistan's democracy. Those who committed this crime must be brought to justice."
The State Department has been heavily involved in attempts to keep the situation in Pakistan calm over the last month and to maintain political stability.
British Foreign Secretary David Miliband voiced shock at Bhutto's killing.
"In targeting Benazir Bhutto, extremist groups have in their sights all those committed to democratic processes in Pakistan. They cannot and must not succeed," Miliband said.
Former Indian Foreign Minister Natwar Singh warned that Bhutto's assassination "is not only bad for Pakistan, it is bad for the entire region."
Bhutto was the daughter of former Pakistani premier Zulfikar Ali Bhutto who was executed. His daughter was flanked by a massive picture of him during her address today.
Benazir Bhutto was a charismatic leader in her own right who twice served as prime minister of the Islamic nation between 1988 and 1996. She was only 35 when first elected Pakistan's leader.
Bhutto has been the target of nine previous assassination attempts.
The Associated Press and Reuters contributed to this report.