GUNMEN in Iraq’s “Triangle of Death” sealed off a crowded market south of Baghdad yesterday and slaughtered almost 60 men, women and children, spraying the crowd with machinegun fire, grenades and mortars, security officials said.

The attack in Mahmudiyah, home to both Shia and Sunni, was so frenzied and sudden that no one was sure what had happened, with some security officials reporting car bombs exploding, others saying that a series of at least eight detonations had been grenades or mortars.

The massacre was unusual in its brazen use of gunmen, who rounded up civilians and murdered them in a public place. It came only a week after Shia gunmen rampaged through a Sunni area of Baghdad, killing more than 40 civilians in daylight, an ominous sign that a new stage of viciousness in the sectarian conflict may have begun. In Baghdad Shia politicians stormed out of parliament in protest at the killings, while a defence ministry spokesman tried to convince reporters that the deaths had been the result of two car bombs, insisting that no gunmen had been involved.

That statement was contradicted by the survivors. “About six cars with at least 20 masked gunmen blocked the market road from two sides, got out of the car and opened fire randomly on women, children and elderly people in the market,” Muzzaffar Jassem, who was evacuated to a hospital in Baghdad, said. “The gunmen controlled the market for more than 15 minutes before they left.”

They left a scene of carnage, with burnt-out hulks of vehicles smouldering among the charred skeletons of market vendors’ stalls.

The attack began at about 9am with a barrage of mortars, swiftly followed by the appearance of the gunmen, who shot dead three Iraqi soldiers at a checkpoint and then sprayed the busy market with automatic weapons fire and rocket-propelled grenades, police said.

Officials were unable or unwilling to identify the attackers, two of whom had a sack of grenades when they were captured in a nearby house. But Muayyad Fadhil, the Shia mayor, said that the killers had emerged from a mainly Shia suburb.

Police said that most of the victims were Shia. Sunni MPs said that the attack could have been revenge for the kidnapping and murder of seven Sunnis whose bodies were found the day before in Mahmudiyah. As Shia politicians walked out in protest the Sunnis blamed the Shia bloc that dominates parliament for failing to secure the country.

Afterwards furious and grieving relatives tussled with Iraqi soldiers trying to control the crowds that gathered to look for survivors. “You are strong men only when you face us, but you let them do what they did to us,” one man shouted.

William Patey, the British Ambassador, said that the slaughter “was a horrific and cowardly act deliberately designed only to provoke further sectarian hatred”.

Zalmay Khalilzad, the US Ambassador to Iraq, gave warning last week that if the newly appointed Iraqi Government did not contain the carnage in the next six months then “there is a risk that the sectarian conflict will expand [and] state institutions will be overwhelmed”.

The massacre in Mahmudiyah came hours after a suicide bombing in the north that killed 28 people in a café. In Baqouba, north of Baghdad, four policemen were shot dead when gunmen stormed a hospital and freed 13 wounded detainees. And in Baghdad the director of the North Oil Company was kidnapped while leaving a meeting at the oil ministry.

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