NEW DELHI — In the deadliest attack in a string of mysterious terrorist assaults in Pakistan, a bomb hidden in the gas tank of a crowded bus exploded Sunday, killing more than 50 passengers and injuring two dozen others, Pakistani officials and media said.
The bus was carrying residents of Punjab province home for Eid al-Adha, the Islamic festival of sacrifice and the most important feast in the Muslim calendar.
Many of the passengers, including women and children, were trapped inside the bus when it burst into flames and were burned to death, some beyond recognition.
There was no immediate claim of responsibility for the bombing, but Prime Minister Benazir Bhutto pointed the finger at India, Pakistan's unfriendly neighbor.
Authorities said the explosive charge detonated as the crowded bus stopped to pick up passengers at a village marketplace in Bhaj Pheru, about 30 miles southwest of Lahore, Punjab's capital.
The state-run Associated Press of Pakistan news agency said the bomb was planted in the bus' gas tank and that it blew up with deafening force.
"There were two explosions--the first one and then a second one almost immediately, I guess when the petrol tank exploded," Ata Dada, a paramedic, told reporters at the scene.
Dada, whose first aid station was only about 200 yards away, said he could see the victims inside the bus, some screaming for help, but that he was helpless to stop the fire. He didn't even have a fire extinguisher.
"We couldn't do anything but watch," he said. "People inside were screaming. It was so horrible."
The bodies couldn't be removed from the gutted vehicle for four hours, he said. "Everything was so hot. We couldn't touch anything."
Twenty-four passengers survived the bombing and fire but sustained serious injuries, news reports said. At least 13 were rushed to a Lahore hospital for emergency treatment.
Whoever was behind the bombing, it was clearly meant to claim the maximum number of lives possible. Pakistanis by the millions travel for Eid al-Adha, the commemoration of biblical patriarch Abraham's sacrifice of a ram as a divine dispensation releasing him from the sacrifice of his son. Any bus targeted on that day was bound to be full.
In a telephone interview with the BBC, Bhutto alleged that the attack could be part of a campaign by India to destabilize Pakistan's largest, most populous and most politically important province.
"The preliminary report indicates that it might have been from outside the country and externally sponsored," she said of the bombing. "We have received reports that these elements would now try to step up activity in the majority province of Punjab."
Bhutto offered no proof of Indian involvement. India, Pakistan's longtime adversary, has always flatly denied any role in fomenting terrorism in Pakistan.
In any event, Punjab has been the scene of deadly confrontations between rival Sunni and Shiite Muslim extremists, and opponents of Bhutto's Pakistan People's Party have been teargassed and beaten by police during marches in Lahore.
Earlier this month, a powerful bomb ripped through the waiting room of a crowded Lahore cancer hospital founded by one of Bhutto's most astringent critics, killing a 12-year-old boy and five men. More than 20 other people were injured.
That April 14 bombing followed growing rumors that the hospital's founder, former cricket great Imran Khan, was going to announce the formation of a political party to challenge Bhutto and the main opposition party, the Pakistan Muslim League.
Many people took the hospital bombing as a warning to Khan to stay out of politics. But last week, he founded the Movement for Justice, providing Bhutto with what may prove to be her strongest political rival to date.
There have been a number of other unexplained bus bombings in Punjab, including an explosion in December at a Lahore bus terminal that killed three men and injured more than 20.