Patrick Cockburn: US soldiers in Iraq kill 250 men from 'apocalyptic cult'

American and Iraqi troops killed about 250 armed men alleged to belong to an apocalyptic Islamic cult who were planning to attack the religious leadership of the Shia in the holy city of Najaf, according to Iraqi political, military and police sources.

The battle took place in the orchards around Najaf and a US helicopter was shot down during the fighting, killing two crewmen. Hundreds of fighters drawn from the Sunni and Shia communities who gathered amid the date palms were followers of Ahmed Hassani al-Yemeni who claims to be the vanguard of the Messiah according to Iraqi politicians. His office in Najaf had been closed 10 days ago.

Details of what happened are sketchy. The US forces used tanks and F-16 fighter bombers. An Iraqi military source said the dead wore headbands declaring them to be "Soldiers of Heaven". The Najaf governor Asaad Abu Gilel said the authorities had discovered a conspiracy to kill some of the senior clergy.

Anarchic violence reached new heights across Iraq. Mortar bombs exploding in the courtyard of a girls' school in west Baghdad killed five children and wounded 21 in the latest atrocity in the escalating sectarian civil war between Sunni and Shia.

"The shrapnel hit her in the eyes and there was blood all over her face ... she was dead," said Ban Ismet, a 15-year-old girl wounded in the legs, speaking in hospital of her friend Maha who was killed by the bomb.

The mortaring of the Kholoud Secondary School in the Adil district was the latest tit-for-tat attack between Shia and Sunni in this highly contested area. The school is Sunni and the killing of the children was most likely carried out by Shia militiamen who have been attacking Adil from the north. Sunni in Baghdad are increasingly being driven into the south-west quadrant of the city.

The school headmistress Faziya Swadi said that two mortar bombs exploded in the courtyard of the school, breaking the windows and spraying the pupils with broken glass as well as shrapnel. The stone steps and pathways were smeared with blood. Hours later weeping parents were placing bodies of their children in wooden coffins.

Wherever Sunni and Shia districts are close together in Baghdad there are frequent killings. Each community sees itself as being the victim of unprovoked aggression. Sectarian animosities are particularly high because the Shia rite of Ashura takes place tomorrow when they commemorate the martyrdom of the Imam Hussein at the Battle of Kerbala in AD680. Hundreds of thousands of Shia are making the three-day pilgrimage on foot from Baghdad to Kerbala.

Seven people were killed yesterday by three bombs, two left in markets and one on a bus, in Shia neighbourhoods.

Some 150 people, mostly Shia, have been killed by bomb attacks in Baghdad over the past week. But probably a majority of the 25 to 50 dead bodies, often bearing marks of torture, that are found by police every morning in the capital are Sunni. This is because the police and police commandos are Shia and often detain and kill Sunni at their checkpoints.

Mixed neighbourhoods are disappearing in the capital. The sectarian cleansing started in 2005 and gathered pace after the destruction of the Shia al-Askarai shrine in Samarra in February 2006. Bomb attacks on Sadr City on 23 November last year killed 215 and wounded 250 more. Shia retaliation led to another mass flight of Sunni. Since there are no Sunni safe havens in Iraq, either in Baghdad or outside, many members of the community are fleeing to Jordan and Syria.

In a sign of the unreliability of the security forces some 1,500 policemen have been sacked in the province of Diyala north-west of Baghdad. The new police chief Ghanim al-Qureishi said the men were fired because they fled instead of fighting when insurgents attacked the provincial capital Baquba in November.