US and Iraqi forces have killed a senior al-Qaeda leader believed to have been behind the kidnapping of the American journalist Jill Carroll and the murder of an American peace activist.

There was a swirl of confusion surrounding the killing of Muhared Adbul Latif al-Jebouri in an ultra-violent area of Baghdad, with Iraqi officials initially identifying him as Abu Omar al-Baghdadi, the head of the Islamic State of Iraq, a coalition of extremist Sunni militant groups that has declared a Caliphate in the lawless areas north of Baghdad.

US officials said al-Jebouri’s body may even have been mistaken for Abu Ayyub al-Masri, the al-Qaeda kingpin who Iraqi forces claimed to have killed earlier in the week.

Major-General William Caldwell, the US military spokesman in Baghdad, said al-Jebouri was killed on Tuesday, the same day that al-Masri was said to have been shot, hinting that Iraqi officials had mixed the two leaders up.

“This is the individual that has caused some confusion and was the senior al-Qaeda person killed,” he said. “His was the only body we took at the site.” US officials had refused to comment on al-Masri’s alleged demise, and his corpse was never recovered. Al-Qaeda denied his death.

Abu Muhammad al-Jebouri, the dead man’s brother, confirmed that the militant leader had been killed in a firefight with US and Iraqi forces in Ghazaliyah, a violent district of west Baghdad where Sunni and Shia gunmen are fighting for supremacy.

A four-man team of militants was trying to take the body back to al-Jebouri’s home town of Duluwiyah, just north of Baghdad, for burial, when they were stopped at an Iraqi army checkpoint in the al-Qaeda stronghold of Tajji. A shoot-out ensued in which two of the gunmen were killed and the other two arrested. The body was eventually seized by the Iraqi troops.

Al-Jebouri, a former military intelligence officer in Saddam Hussein’s army, had been named “information minister” of the Islamic State of Iraq. He was believed to have been responsible for kidnapping Ms Carroll in January 2006, and for the abduction and murder of Tom Fox, an American Christian peace activist seized together with Norman Kember, a British member of the Christian Peacemaker Team. Al-Jebouri was involved last year in kidnapping two Germans in Beiji, northern Iraq.

The Islamic State of Iraq was declared last autumn by a coalition of al-Qaeda-linked and hardcore Sunni insurgent groups. It is focused on Diyala province to the northeast of Baghdad, although it lays claim to six other governorates including Baghdad.

The aim of the “state” is to recreate a Sunni land in the image of Arabia at the time of the Prophet Muhammad, turning back the clock in a way that the Taleban tried to do in Afghanistan.

The puritanical movement enforces a rigorous version of Salafist Islam, banning men from shaving their beards, having short hair like American soldiers or even smoking. Men caught repeatedly smoking have their index fingers rammed into metal pipes and then snapped, while cigarette shops have been torched.

The rules have often been taken to absurd extremes. Greengrocers in the Caliphate told The Times they had been ordered not to sell bananas in public because they were deemed obscene, while for similar reasons cucumbers could not be sold next to tomatoes, which are deemed to represent femininity.

At the most extreme level, shepherds have even been ordered to cover the nether regions of their goats to avoid offending strict Salafist sensibilities. A doctor from Baquba who recently spoke to The Times said he always written off such absurd tales as rumours. But driving in a shared taxi through a village near the provincial capital of Diyala he saw a goat wearing boxer shorts and started laughing.

“The other passengers told me to shut up, or it could cost me my life,” he said.

Edicts have also been issued banning the use of ice, as the Prophet would not have had access to chilled water. While seemingly ridiculous, the rules are often enforced by brutal extremists who fail to see the absurd side of their regime.

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