THE first to die was Ammar, gunned down on his way to university. Later, Fares, a day labourer, was also shot dead.

Nobody initially linked the killings to the new Shia mosque being built in al-Khadra, a predominantly Sunni area of west Baghdad.

The deaths of the two men, who were donating money and material to the project, were initially lost in the blizzard of violence that enshrouds the capital.

It was only after Sayyid Bassem, who had received a warning to pull out of the project or be killed, was shot that the other sponsors of the mosque realised what was happening. Three more sponsors were murdered in the subsequent months, usually by armed men in BMWs — the guerrillas’ transport of choice which Baghdadis have dubbed the Mujahidin Humvee.

“When we realised this was happening, we got really scared,” said Ali Monam, 31, a clerk. Like other backers of the mosque, he decided to get out before a BMW tracked him down too. He took his wife, a Sunni, and their baby and moved to a Shia area of the city.

Across Baghdad sectarian violence was redrawing the city map well before the frenzied killing spree that followed last week’s bombing of the Shia mosque in Sammara. Shias were moving from Sunni to Shia areas, and vice versa, in what some Iraqi officials regard as a form of “ethnic cleansing”.

The International Crisis Group served warning yesterday that the “Sunni-Shiite schism . . . threatens to tear the country apart”.

In a report entitled The Next Iraqi War?, it said that the scenes of mayhem that followed the Samarra bombing were “only the latest and bloodiest indication that Iraq is teetering on the threshold of wholesale disaster”.

“Iraq’s mosaic of communities has begun to fragment along ethnic, confessional and tribal lines, bringing instability and violence to many areas,” it said. “Its most visible manifestation is a dirty war being fought between a small group of insurgents bent on fomenting sectarian strife by killing Shiites, and certain government commando units carrying out reprisals against the Sunni Arab community.”

The silent and insidious process of segregation cuts both ways. In a Sunni district of Baghdad called Radwaniyah, Imad al-Hamdani told The Times of the deadly pressure that drove him from his home in a Shia part of Amel, a mixed district in the south of the capital where about 40 Sunni families lived.

“All the Sunni families have left now because of both governmental and local intimidation,” he said, referring to death threats, regular house raids by security forces under the control of the Shia-dominated Interior Ministry, the arrest and torture of Sunni men and the murder of more than thirty-five shopkeepers in just three months last summer.

“It happened in a very organised way,” he said. “It started when Interior Ministry commandos conducted a very big operation in my neighbourhood. They raided all the Sunni houses in one night, and arrested all the men.”

Mr al-Hamdani was arrested with his brothers and brother-in-law. He said that the latter had been tortured so badly — he had holes drilled in his chin, his back fractured and legs broken — that he died in custody.

“They kept torturing us for nearly three weeks without interrogating us, or telling us why we were there,” he said. “Then they took me and my brothers to the interrogation room. The interrogator said to us that we should leave the area where we live and move to another one because we were Sunni.”

The situation in Amel only deteriorated, with more frequent house raids by troops, and more death threats. “Then the commandos started raiding our houses almost every night, and in one week 23 Sunnis were killed in my area. We didn’t feel safe to stay.” Now most Sunni houses in Amel are empty and have For Sale painted on their walls. The families all decided to leave in less than ten days, many of them abandoning furniture and clothes.

Mr al-Hamdani cannot buy a new house until he sells his old one. Meanwhile he, his wife and children live in one room in a relative’s house, and he travels two hours back to Amel each day to open his shop. Even then, he sits in a neighbouring shop with a gun, using Shia friends to serve his customers to avoid assassination.

Neither Mr al-Hamdani nor Mr Monam have gone to the police for fear that they too be implicated in the sectarian cleansing. And Mr Monam, with his Sunni wife, is reluctant to go to a Shia militia to seek protection. “If I get a militia in, it means I’m starting a war in my own house,” he said. “If things go on like this, there will be pure Sunni and Shia areas.” And his mosque now stands as abandoned as Mr al-Hamdani’s house.

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