A policeman stands guard near a burning vehicle after a gunfire attack in Baghdad yesterday. Gunmen attacked a police patrol, killing two policemen and wounding two others yesterday, police said. - Reuters

BAGHDAD (Reuters):

Car bombs killed more than 200 people in Baghdad yesterday in the deadliest attacks in the city since U.S. and Iraqi forces launched a security crackdown aimed at halting the country's slide into civil war.

One car bomb alone in the mainly Shi'ite Sadriya neighbourhood killed 122 people and wounded 155, police said.

"The street was transformed into a swimming pool of blood," Ahmed Hameed, a shopkeeper near the scene, told Reuters.

U.S. Defence Secretary Robert Gates, speaking in Tel Aviv on a visit to the region, called the bombings "horrifying", and indicated Sunni Islamist al Qaida was to blame.

The apparently coordinated attacks - there were four within a short space of time - occurred hours after Shi'ite Prime Minister Nuri al-Maliki said Iraq would take security control of the whole country from foreign forces by the end of the year.

Maliki is under growing pressure to say when foreign soldiers will leave, but the attacks in mainly Shi'ite areas of Baghdad underscored the huge challenges for Iraq's security forces in taking charge of overall security from more than 150,000 U.S. and British troops.

More than 200 wounded

The bombings wounded more than 200 people.

"I saw dozens of dead bodies. Some people were burned alive inside minibuses. Nobody could reach them after the explosion," said a witness at Sadriya, describing scenes of mayhem at an intersection where the bomb exploded near a market.

"Women were screaming and shouting for their loved ones who died," said the witness who did not wish to be identified, adding many of the dead were women and children.

One man waving his arms in the air screamed hysterically: "Where's Maliki? Let him come and see what is happening here."

U.S. and Iraqi forces began deploying thousands more troops on to Baghdad's streets in February.

Sectarian death squad killings have declined, but car bombs are much harder to stop, U.S. military officials say.