Iraq-US crackdown to tame Baghdad rebels

The crackdown comes after Al-Qaeda warned of massive attacks to avenge last week's death of its leader Abu Musab al-Zarqawi in a US air raid and also a day after an unannounced visit by US President George W. Bush to Baghdad.

Iraqis in Baghdad were forced to double their commute time as new checkpoints mushroomed after the defense ministry announced that some 40,000 security forces, both Iraqi and coalition, would secure the city in Operation Forward Together.

Baghdad province is home to seven million people, a quarter of the country's population, and is one of the most unstable areas in the country.

There were traffic jams throughout the city as commuters waited in long lines in front of checkpoints that stopped most cars instead of waving people through as before.

The ministry did not specify how long the new security measures would be in place and the prime minister publicly asked for patience.

Checkpoints were being manned by different branches of the security services, with some handled by the police, some by the commandos or national police and others the Iraqi army.

US forces are also involved, mostly in a support role, providing air cover and roving patrols.

"We are supporting Iraqi security forces in this security plan and we are carrying out operations in the capital," said coalition forces spokesman Major William Wilhoite, who declined to comment on how many US troops were involved.

Officers at the checkpoints were stopping drivers and checking their cars, registration documents and identity papers.

Single male drivers received special attention especially if they were driving vehicles without license plates in the BMW or Opel models favored by insurgents.

Cars with women and children and public buses were generally waved through.

The plan will also include house to house searches of areas suspected of hiding insurgents as well as a crackdown on civilians carrying weapons -- a tall order in militia-run Baghdad neighborhoods like Sadr City.

In fact, residents of that Shiite neighborhood of over two million said that no checkpoints had been set up inside their district, but only on the outskirts.

The nighttime curfew also has been extended two and a half hours so that it begins at 8:30 pm (1630 GMT) until 6:00 am (0200GMT) while a vehicle ban will be in place during afternoon prayer hours on Friday.

However the new measures did not prevent at least two people being killed seven wounded in a car bomb targeting an Iraqi army patrol in Baghdad's northern Al-Qahira neighborhood.

On Tuesday Bush made a lightning visit to Baghdad to offer his unflinching support in battling Iraq's raging insurgency, but said the country's future was in its own hands.