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RAWALPINDI- The assassination of opposition leader Benazir Bhutto has sparked violent protests across Pakistan, with angry supporters burning property and firing shots.
Paramilitary forces have been put on "red alert" throughout the country.
Bhutto, 54, was attacked as she left an election rally in the city of Rawalpindi and died in hospital. Her husband and three children later took Bhutto's body to her ancestral home for burial.
Police said the attacker fired shots at Bhutto before blowing himself up. Sixteen people died in the blast.
President Pervez Musharraf denounced the "terrorist attack" and appealed for calm after Bhutto's angry backers took to the streets across Pakistan after her death.
In Sindh, the family stronghold where the Oxford- and Harvard-educated Bhutto had a huge following, mainly amongst the poor, police said they were patrolling all towns and cities.
"There is trouble almost everywhere," a senior police official said.
In the province's capital, Karachi, thousands took to the streets. At least three banks, a government office and a post office were set on fire, a witness said.
Tyres were set on fire on many roads, and shooting and stone-throwing was reported in many places. Most shops and markets in the city shut down.
At least 20 vehicles were torched in the central Sindh town of Hyderabad.
There were also small protests in Rawalpindi and the nearby capital, Islamabad.
Bhutto, who inherited the political dynasty started by her father Zulfikar Ali Bhutto - who was hanged in 1979 after a military coup - had hoped to win an election set for January 8, giving her a chance to become prime minister for the third time.
"It is the act of those who want Pakistan to disintegrate because she was a symbol of unity," said Farzana Raja, a senior official from Bhutto's Pakistan People's Party.
"They have finished the Bhutto family. They are enemies of Pakistan."
It was not immediately clear whether Musharraf could decide to postpone the election and reimpose a state of emergency that was only lifted on December 15 after six weeks.
Body taken for burial
People cried and hugged each other outside the hospital where she died in Rawalpindi, a garrison city which is home to the Pakistan army.
Some shouted slogans against President Pervez Musharraf, who seized power in a military coup in 1999 but has since stepped down from the army.
Bhutto's main political rival, former prime minister Nawaz Sharif, told the crowd he was as upset as them. "My heart is bleeding and I'm as grieved as you are."
Hundreds of distraught supporters bore Bhutto's plain wooden coffin aloft from the hospital to an ambulance that carried it to a military airport.
"The body has been flown to Sindh along with the family and 35 relatives and supporters," a security official said.
According to Islamic tradition, funerals should be held as quickly as possible. Party officials said they expected the funeral would be held on Friday local time.
Party officials said Bhutto would be buried in her native village of Garhi Khuda Baksh, in Larkana district, in her family graveyard next to her father, Zulfikar Ali Bhutto.
"She has been martyred," said party official Rehman Malik.
Musharraf condemned "in strongest possible terms the terrorist attack that resulted in the tragic death of Bhutto and many other innocent Pakistanis", Pakistan's state news agency said.
Police said 16 people had been killed in the attack on Bhutto. "The man first fired at Bhutto's vehicle. She ducked and then he blew himself up," said police officer Mohammad Shahid.
It was the second attack on Bhutto in under three months. On October 19 a suicide bomber killed nearly 150 people as she paraded through Karachi on her return from eight years in exile.
On Thursday, Bhutto had told of the risks she faced.
"I put my life in danger and came here because I feel this country is in danger. People are worried. We will bring the country out of this crisis," Bhutto told the Rawalpindi rally.
Worldwide condemnation
The attack brought widespread condemnation from around the world.
The United States, which sees Pakistan as a key ally in its battle against al Qaeda, had championed Bhutto as a popular leader who might help return the country to a civilian-led democracy after nearly a decade of military rule.
"The United States strongly condemns this cowardly act by murderous extremists who are trying to undermine Pakistan's democracy," President George W. Bush said in a statement.
He urged Pakistanis to honour Bhutto's memory by continuing with the democratic process.
India, Pakistan's giant neighbour and rival, said Bhutto's assassination was a terrible blow to the democratic process.
"In her death the subcontinent has lost an outstanding leader who worked for democracy and reconciliation in her country," said a spokesman for Prime Minister Manmohan Singh.
Bhutto became the first female prime minister in the Muslim world when she was elected in 1988 at the age of 35. She was deposed in 1990, re-elected in 1993, and ousted again in 1996 amid charges of corruption and mismanagement.
She said the charges were politically motivated.
Bhutto family's history of violence
* Benazir Bhutto's father, Zulfikar Ali Bhutto, became the country's first popularly elected prime minister but was toppled by the military in 1977 and later hanged for the murder of a political opponent. His supporters said the charge was trumped up by a military dictator.
* Both of his sons died in unexplained circumstances. Shahnawaz Bhutto, the younger son, was found dead in his flat on the French Riviera in 1985. Benazir said her brother was poisoned. The older son, Murtaza, was killed along with six supporters after a confrontation with police in Karachi in 1996. His family says it was a targeted killing.
* Zulfikar Ali Bhutto's bed-ridden wife, Nusrat, and an apolitical daughter, Sanam, are the only survivors of the family.
* Benazir Bhutto was lucky to survive when a suicide bomber killed nearly 150 people in an attack on her motorcade as she returned to the country in October after eight years in exile.
* Later that month, she paid an emotional return to her father's grave in their ancestral village in southern Pakistan. "There is still danger of attack, but Allah can protect everyone and I am not scared," she said.
* In a family interview with India's Outlook magazine in Dubai last year, Benazir said she hoped her three children would choose a different career. "My children have told me they are very worried about my safety. I understand those fears. But they are Bhuttos and we have to face the future with courage, whatever it brings."
- REUTERS