At least 59 dead and scores injured in double suicide bomb at Pakistan arms factory

The bombers blew themselves up almost simultaneously outside two gates of the heavily-guarded complex, where about 25,000 workers produce explosives, ordnance and weapons.

Pakistani Taliban claimed responsibility for the outrage, in which 70 were wounded.

Blast: Pakistani security officials at the site of the bombings, which killed at least 57

It is the second suspected terrorist incident in the country since President Pervez Musharraf resigned on Monday, leaving behind a divided coalition government.

Soldiers and police cordoned off the area after the attack, as ambulances raced to the scene to deal with the casualties.

Pakistani Taliban spokesman Maulvi Umar said the attacks were in revenge for military airstrikes in Bajur, a militant stronghold near the Afghan border.

Umar warned militants would carry out similar attacks in other major cities, including the capital of Islamabad, unless the military halts its operations.

Security forces are involved in an escalating war with Islamic extremists in two nearby regions of northwestern Pakistan.

Rana Tanveer, who was working at a bank about 200 meters from one of the gates where a bomber struck, said he was among the first to reach the scene.

'All around the gate I saw blood and human flesh. People helped the injured and took them in their cars and even on motorbikes to the hospital,' he said.

'Seven or eight people were already dead and another 10 people were breathing their last.'

Resignation: President Musharraf stood down earlier this week

The factory lies on the road into Pakistan's troubled northwest, where fighting between security forces and Islamic militants has escalated in recent weeks.

Militants have repeatedly threatened to restart a bombing campaign that raged across the country last year unless the army pulls back.

Musharraf, who had been a key supporter of the U.S. war on terrorism, resigned on to dodge the humiliation of impeachment following nearly nine years in power.

The coalition government, meanwhile, has plunged back into a struggle over how to restore dozens of Supreme Court judges he sacked last year to avoid legal challenges to his rule.

The maneuver deepened his unpopularity, propelling his rivals to victory in parliamentary elections five months ago, and turned the judges into controversial political figures.

Former Prime Minister Nawaz Sharif's party today threatened to leave the ruling coalition unless the judges were quickly reinstated.

And the coalition's biggest bloc, the Pakistan People's Party, appeared to be lining up smaller parties to keep control of parliament in case that happened.

'The future of this coalition is linked to the restoration of judges,' Sharif's spokesman Sadiqul Farooq said. 'If the judges are not restored, we will prefer to sit on opposition benches.'

Sharif wants to restore the all the justices, who could help him if he decides to seek revenge against Musharraf, who ousted the former premier in a 1999 coup, jailed him and then banished him to exile in Saudi Arabia.

But Asif Ali Zardari, the leader of the Pakistan People's Party, is less enthusiastic. He has accused former chief justice Iftikhar Mohammed Chaudhry of being too political.

Analysts say he also may be worried the former chief justice would revive corruption cases against him or facilitate legal action against Musharraf - a destabilizing move sure to dismay the country's Western backers, especially the United States.

The People's Party said it was committed to restoring the judges but that it had other priorities as well, including improving the lives of ordinary Pakistanis who are struggling with chronic food and fuel shortages.

'We hope the coalition will not break,' Farzana Raja, the ruling party's spokeswoman told Pakistani Waqt news channel.

The coalition also must seek agreement on a candidate for the presidency. The new leader must be elected by lawmakers by mid-September.

The People's Party insisted this week that, as the largest party in the coalition, it has the right to choose the new head of state, something unlikely to go over well with Sharif.

Though they have yet to name a candidate, party members were talking up a candidacy for Zardari, who comes from the well-off southern province of Sindh.

Sharif's party was arguing for a president from one of the smaller province - Baluchistan or North West Frontier - in order to strengthen Pakistan's strained federation.