Market vendors in Sadr City spent yesterday morning clearing blood and body parts from pavements and stalls after a bomb blast that killed 78 people in the Shia area of Baghdad.

This bomb, after another in Kirkuk province at the weekend, in which 70 died, was the deadliest in Iraq for more than a year. Many fear that it heralds an intense period of violence as US troops withdraw from the cities before the June 30 deadline.

A limited number of US soldiers will remain to train local security forces.

“What the hell is the Government doing?” said the proprietor of an electronics shop. "The Iraqi Army do nothing at all. They spend their entire duty time fiddling with their mobile phones.”

A checkpoint near the market, which the previous night had allowed the motorcycle laden with explosives into the crowded area, was not manned properly, he said. The men on duty had let another similar vehicle, laden with vegetables, come through that morning without searching it.

He expected more violence as troops withdrew: “Things will increase because I can’t see any real measures the State is taking for me.”

Nouri al-Maliki, the Iraqi Prime Minister, tried to reassure his compatriots and urged them to pass on any information of potential attacks to combat “a plan that aims to awaken sectarianism, create chaos, abort the political process and prevent Iraqi people from standing on their own feet”.

Robert Gibbs, the White House spokesman, said there were no plans to change the withdrawal date.

At least 11 people died and nearly 50 were wounded by bomb attacks in Baghdad yesterday. In Fallujah a roadside bomb killed five policemen.

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