String of Iraq rebel attacks follows arrest of al-Qaeda suspects

US troops announced the arrest of 60 suspected members of a car bomb cell after swooping on a funeral ceremony near where a 5,000-strong US-Iraqi joint force is conducting a major house-to-house sweep to flush out so-called death squads.

The US-led coalition said those captured in the raid were thought to be linked to the Sunni extremist movement al-Qaeda in Iraq, which is inspired by Osama bin Laden's network and which has killed hundreds of civilians.

They were "detained without incident" on Friday after intelligence data led troops to a funeral in Arab Jabur, on the southern edge of Baghdad.

Arab Jabur is a Sunni area close to the restive Dura district, which was this week the focus of a massive joint Iraqi-US operation designed to cordon off flashpoint areas, conduct weapons searches and root out armed gangs.

Since February, when a bomb attack against a Shiite mosque in Samarra, triggered a wave of tit-for-tat sectarian killings, Baghdad has been in the grip of an urban dirty war between rival Sunni and Shiite extremist groups.

"Operation Together Forward" has put more than 50,000 Iraqi troops and police and more than 10,000 Americans into the fray in a bid to quell the violence, which leaves around 50 people dead every day.

Last week US generals said the violence could push Iraq into civil war.

Observers warn that this new "Battle of Baghdad" represents Prime Minister Nuri al-Maliki's last chance to impose the authority of his national unity government and avert the fragmentation of his country.

US-led forces also announced the arrest of "a new senior al-Qaeda in Iraq leader in the Baiji terrorist network" in Baiji, 200 kilometres (140 miles) north of Baghdad, accusing him of sending killers to Baghdad.

At the same time, however, violent attacks continued around the country.

In Baquba, north of the capital, attackers shot dead a police captain as he was heading in to work and separately detonated a roadside bomb, injuring seven officers conducting a patrol, police said.

Two civilians were also killed by drive-by shootings in the town.

Meanwhile, in Baghdad proper, five officers were injured when a roadside bomb detonated in the Adhamiyah district in the north of the city. No one was killed, an interior ministry official said.