BAGHDAD, June 17: Two car bomb attacks against Iraq's army and civil defence corps on Thursday killed 41 people and wounded 145 others as insurgents aimed to sow chaos ahead of the June 30 transfer of sovereignty.

As violence spiralled out of control, UN Secretary-General Kofi Annan warned the security situation was too dangerous for the world body to return to Iraq. It was not clear how his announcement would affect the crucial UN role in helping prepare Iraq for January elections, the cornerstone of US ambitions to create a showcase for democracy in the Middle East.

In the deadliest attack this month, a suicide bomber rammed a white sports utility vehicle, packed with artillery shells, into a Baghdad army recruiting centre Thursday morning, killing 35 people and wounding 141 others.

Bloodied and battered bodies, many of them volunteers who had been queuing up to join the New Iraqi Army, lay tangled in the street after the blast. Rescue workers heaped mutilated casualties into ambulances and police trucks, while dazed men in Iraqi military uniform stood by watching and shouting helplessly.

"A suicide bomber, his hands clutching the steering wheel, launched his car, loaded with explosives, against the people who were waiting in front of the centre," said army commander Khaled Jamal Said.

"It is criminal, that is all I can say." In February, a car bomb targeted the same recruitment centre, killing 47 people, most of them young volunteers. The US-led coalition had warned of a surge in violence as the clock ticks down to the return of sovereignty to an Iraqi administration.

Since the fall of dictator Saddam Hussein in April 2003, thousands of Iraqis have died as insurgents waged a low-intensity war against the US-led coalition. Iraq's prime minister Iyad Allawi, battling attempts to discredit his new government, visited the bombing site, surrounded by a host of security guards.

He accused foreign countries, without naming them, of being behind the devastation. The US boss in Iraq, Paul Bremer, linked the attack with Al-Qaeda operative Abu Mussab al-Zarqawi.

"It certainly is consistent exactly with what Zarqawi said he would do back in January," he said, referring to a letter purportedly from the fugitive Islamist detailing plans to foment civil war in Iraq.

Naked bodies lay in the dirt behind the sandbagged barricades of the recruitment centre that were meant to shield volunteers from attack. A corpse dangled out of an abandoned car, his brain lying beside him in the passenger seat.

"About 100 of us were standing in front of the Iraqi army recruitment centre," said Issam Jassem, 32, a former member of Saddam's disbanded forces. "An officer was in the process of reading out a list of people accepted to take part in the new army and had told us that we had to return on June 26 when the explosion happened," the young volunteer said.

Mohammed Habib, a 20-year-old labourer, said from his hospital bed: "A strange man, wearing a fundamentalist-style robe and white skull cap, approached the line. "He studied us for a moment and glanced away for a minute. Just before the explosion, he disappeared."

Jamal al-Ani, director of emergency operations at Iraq's health ministry, said the casualty toll stood at 35 dead and 141 wounded. Many of the wounded were fighting to stay alive.

Since a new Iraqi caretaker government backed by the United States was unveiled on June 1, Iraq has seen at least 20 car bombs and the deaths of more than 180 people. Three hours after the Baghdad attack, six Iraqi civil defence soldiers were killed and four wounded in a car bombing north of Baghdad, a military spokesman said. -AFP