Christians Under Attack

In fact, many of the wounded were almost certain to die because one of the doctors at the Republic Hospital was a member of an insurgent cell. Pretending to treat the injured men, he killed 43 of them by secretly administering lethal injections, a police inquiry has revealed.

"He was called Dr Louay and when the terrorists had failed to kill a policeman or a soldier he would finish them off," Colonel Yadgar Shukir Abdullah Jaff, a senior Kirkuk police chief, told The Independent. "He gave them a high dosage of a medicine which increased their bleeding so they died from loss of blood."

Dr Louay carried out his murder campaign over an eight to nine-month period, say police. He appeared to be a hard working assistant doctor who selflessly made himself available for work in any part of the hospital, which is the largest in Kirkuk.

He was particularly willing to assist in the emergency room. With 272 soldiers, policemen and civilians killed and 1,220 injured in insurgent attacks in Kirkuk in 2005, the doctors were rushed off their feet and glad of any help they could get. Nobody noticed how many patients were dying soon after being tended by their enthusiastic young colleague.

Dr Louay was finally arrested only after the leader of the cell to which he belonged, named Malla Yassin, was captured and confessed. "I was really shocked that a doctor and an educated men should do such a thing," said Col Jaff.

The murderous work of Dr Louay is symbolic of the ferocity of the struggle for the oil province of Kirkuk. The dispute over its fate is the most important reason why the political parties in Baghdad have failed to create a new government three months after the election on 15 December. The Kurds, expelled from Kirkuk and replaced with Arab settlers by Saddam Hussein, captured the city on 10 April 2003. They have no intention of giving it up. "We will never leave Kirkuk," said Rizgar Ali Hamajan, the former Kurdish peshmerga (soldier) who heads the provincial council. "It is part of Kurdistan."

He recalls that when he was 18 months old, his parents fled with him from his village north of Kirkuk moments before the Iraqi army destroyed it.

But Ibrahim al-Jaafari, the Prime Minister, has frustrated Kurdish demands, enshrined in the new constitution, for Kurds to be allowed to return to Kirkuk and Arabs settlers to be removed to their original homes. The Kurds expect a referendum in Kirkuk that would lead to the province joining the highly autonomous Kurdish region ruled by the Kurdistan regional government in northern Iraq.

For the 1.9 million Kurds, Turkomens and Arabs of Kirkuk province, oil has brought few benefits. They live on top of at least 10 billion barrels of oil which was first exploited in 1927. Despite that, people wanting to buy petrol in Kirkuk wait all day in queues of battered vehicles. "It is the most devastated city in all Iraq," said Mohammed Othman, deputy head of the Patriotic Union of Kurdistan, the most powerful Kurdish party in Kirkuk.

All Iraqi provinces were seriously damaged under Saddam Hussein but few on the scale of Kirkuk. Sinister mounds in the fields mark where Kurdish villages once stood before they were destroyed. Often the Iraqi army poured concrete into the village wells to prevent people returning. Saddam Hussein also bulldozed four districts in Kirkuk after the failed Kurdish uprising in 1991. Between then and 2003 at least 120,000 Kurds and Turkomens were expelled, in addition to those forced out in the previous 40 years.

Some Kurds have returned, but not to a land of plenty. In the old sports stadium in Kirkuk, hundreds of families are squatting amid the garbage and sewage. The guerrilla war continues at a low but persistent level and the Arabs are not going to leave or be marginalised without a fight.

Smoke was rising over Kirkuk this week as children set ablaze tyres to celebrate the Nowruz, the Kurdish spring festival.

Kirkuk is not a place where many people would like to live - but the battle to control it may yet destroy Iraq.

By Patrick Cockburn in Kirkuk