Just hours before the blasts, which were claimed by the Pakistani Taliban as a response to army attacks on militants, a key party in the government coalition threatened to quit in a power struggle that has dismayed many Pakistanis and the country's Western backers.
Workers were streaming through two gates of the sprawling factory complex in Wah, 20 miles west of Islamabad, during a shift change about 2 p.m. when the bombers attacked outside the walls.
The force of the explosions knocked many people to the ground and sprayed others with shrapnel.
"I looked back and saw the limbs of my colleagues flying through the air," said Shahid Bhatti, 29, his clothes soaked in blood.
"It was like a doomsday," said Ghaffar Hussain, whose nephew was killed. "We are finished, we are ruined," he said, tears rolling down his face.
Emergency workers with plastic bags on their hands lifted mangled and blackened corpses onto stretchers, while forensic teams picked through scraps of flesh and scattered shoes outside the complex, which employs some 25,000 people making rifles, machine guns, ammunition, grenades and tank and artillery shells.
Tanvir Lodhi of the Pakistan Ordnance Factories said 59 people died. Seventy others were wounded, said Mohammed Azhar, a hospital official.
Nine days earlier, the Taliban declared "open war" on the military over an offensive against militants in the Bajur region.
The declaration was issued after a bomb killed 14 people in an air force truck in Peshawar, the main city of the restive frontier along the Afghan border.
Maulvi Umar, a spokesman for Pakistani Taliban groups, told The Associated Press on Thursday that the arms factory attack was to avenge airstrikes on militants in Bajur tribal area, an extremist stronghold in the mountainous frontier region.
More bombings will be carried out in major cities, including the capital and the southern metropolis of Karachi, unless the offensives are halted, he said.
Prime Minister Yousaf Raza Gilani appealed to lawmakers to urgently draw up a national strategy against terrorism "even if you have to sit together for a week."
"The threat that we are facing today has no precedent," he said before the bombings, addressing a ceremony for police officials who received counterterrorism training through the U.S. State Department. "Our enemy lurks silently within our society. This is our war."
President Bush called Gilani to express sympathy for those killed in recent terrorist attacks in Pakistan.
The two men "reaffirmed their mutual support for going after these extremists that are a threat to both Pakistan, the United States and the entire world," said Gordon Johndroe, spokesman for the White House's National Security Council.
Musharraf, who also received a call Thursday from Bush, resigned Monday to avoid the humiliation of impeachment after nearly nine years in power that began with a boodless coup.
While the former military commander was considered a vital member of Washington's war-on-terrorism coalition, the new civilian government drew U.S. criticism for giving priority to striking peace deals with militants when it came to power five months ago.
The peace effort was popular with many Pakistanis who are angry over the conflict's toll on civilians. But it has met only limited success, and the government is again pursuing military operations against militants in the rugged region along the Afghan border.
The attack in Wat was the country's deadliest since former prime minister Benazir Bhutto narrowly escaped a double suicide bombing in Karachi that killed about 150 people at a parade welcoming her back from exile in October. A gun and suicide-bomb attack killed her Dec. 27.
Amid the violence, the coalition government appeared to be veering toward collapse.
The two main parties, led by Asif Ali Zardari and former Prime Minister Nawaz Sharif, worked together to hound Musharraf into quitting.
But before Musharraf's coup in 1999, the parties fought bitterly over power during years of civilian governments known for corruption and economic mismanagement, and with Musharraf gone many people think their alliance will unravel.
Since Monday, the parties have publicly squabbled over who should succeed Musharraf and over how to restore Supreme Court judges he fired last year.
Sharif's party threatened Thursday to leave the ruling coalition unless the judges are quickly reinstated. Zardari's Pakistan People's Party, which leads the coalition, appeared to be lining up smaller parties to keep control of parliament.
"The future of this coalition is linked to the restoration of judges," Sharif's spokesman, Sadiqul Farooq, told the AP. "If the judges are not restored, we will prefer to sit on opposition benches."
Sharif, bitter over this 1999 ouster and exile by Musharraf, has pressed hard for the return of the judges, which he sees as potential allies for his campaign to charge Musharraf with treason.
But Zardari, widower of the slain Bhutto, is less enthusiastic, worrying that legal action against the former president would be a destabilizing move. Like Musharraf, he has accused former chief justice Iftikhar Mohammed Chaudhry of being too political.
Analysts say Zardari also might fear that Chaudhry would revive corruption cases against him. Musharraf killed off the cases against Zardari and his wife as part of a failed effort to form a pro-Western power-sharing deal with Bhutto before her assassination.
