BAGHDAD (AFP) – A suicide bomber blew himself up at a crowded army recruitment centre in Baghdad killing 59 people Tuesday, officials said, as violence coinciding with the Muslim holy month of Ramadan raged across Iraq.

The attack, the deadliest this year, wounded at least another 100 people and came a day after Iraq's two main political parties suspended talks over the formation of a new government five months on from elections, and as the US withdraws thousands of its soldiers from the country.

"We have received 59 corpses this morning," an official at Baghdad morgue said, speaking on condition of anonymity. A doctor at Medical City hospital, close to the scene of the attack, said they had so far received 125 wounded.

The bomber blew himself up around 7:30 am (0430 GMT) at the centre, a former ministry of defence building that now houses a local security command, in the Baab al-Muatham neighbourhood of central Baghdad.

An interior ministry official said the majority of the victims were army recruits but that some soldiers who were protecting the recruitment centre compound were also among the casualties.

"After the explosion, everyone ran away, and the soldiers fired into the air," said 19-year-old Ahmed Kadhim, one of the recruits at the centre who escaped unharmed from the attack.

"I saw dozens of people lying on the ground, some of them were on fire. Others were running with blood pouring out."

Kadhim said the recruits had been divided into groups based on their educational qualifications, with the suicide bomber targeting the selection of high school graduates.

"I don't know how he managed to get through all the security measures," he added, referring to two searches that each recruit had to pass before being allowed in the area. "Maybe he hid in the area from last night."

Iraqi security forces cordoned off the area following the attack, and security was stepped up across the capital, leading to traffic gridlock during the morning rush hour.

Also on Tuesday, two separate bomb attacks against judges in Baghdad and the central city of Baquba left four of them wounded, security officials said.

The recruitment centre explosion was the bloodiest single attack in Iraq since December 8, when a series of coordinated blasts in the capital killed 127 people.

Violence has surged in the past two months in Iraq, with 200 people already killed in August alone and Iraqi government figures saying that 535 people died in July -- the deadliest month in Iraq since 2008. The US military disputes the July figure, saying 222 people died violently.

Violence has surged since the start of Ramadan on August 11, with a spate of weekend bombings and shootings killing 18 people and a car bomb attack on Tuesday killing five, including four Iranian pilgrims.

The bloodletting has sparked concern that local forces are not yet prepared to handle the country's security on their own.

American commanders, however, insist, that Iraqi soldiers are up to the job as they pull out thousands of their forces ahead of a declaration to an end to combat operations at the end of August.

But Iraq's top military officer has raised doubt about his soldiers' readiness when the last US troops depart as scheduled at the end of 2011. American forces would need to stay until 2020, Lieutenant General Babaker Zebari said earlier this month.

Iraq is also mired in a political stalemate, with the winner of its March election breaking off talks with his main rival Monday evening, dampening already faint hopes that a government could be formed before Ramadan ends in the middle of September.

The country's security forces have been persistent targets at the hands of insurgent groups since the US-led invasion that ousted Saddam Hussein in 2003, as they are seen by militants as a symbol of the government, and representatives of an "occupying force."