A car bomb killed six people and wounded 14 Wednesday in northwestern Baghdad, police said, and U.S. and Iraqi forces raided a hospital in Ramadi they suspect is a base for insurgents.

The blast occurred in mid-afternoon about 300 yards from a Sunni mosque. The neighborhood has a mixed Sunni-Shiite population and the target was unclear.

U.S. spokesman Maj. Gen. William Caldwell predicted an increase in vehicle bombings in the Baghdad area now that Abu Hamza al-Muhajer has succeeded the late Abu Musab al-Zarqawi as head of Al Qaeda in Iraq.

Vehicle bombs are a specialty of al-Muhajer, also known as Abu Ayyub al-Masri, Caldwell said.

The Saddam Hospital that forces raided has been used as a launchpad for mortar attacks and sniper fire against coalition forces, as well as violence against Iraqi civilians, the military said.

"The hospital has also been the scene of murders and intimidation against the people of Ramadi by terrorists," U.S. Col. Sean MacFarland, commander of coalition forces in the volatile area, said in a statement.

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The coalition security forces began searching the hospital in the northern half of the city early Wednesday, the military said, adding that the operation had national and local government approval and was being led by the Iraqi army.

Lt. Col. Stephen Neary said the hospital had been used as a "safe haven and a place to coordinate attacks" by insurgents, who had been observed fleeing to the facility after fighting to regroup and treat their wounded.

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"This Iraqi army-led operation will deny the insurgents the use of the Saddam Hospital and will facilitate the return of the Iraqi police to their former post located in the hospital," he said.

The military stressed it would leave the hospital as soon as possible and said extensive planning was conducted to "ensure appropriate health care continues to be provided."

U.S. and Iraqi forces have recently stepped up their presence in the insurgent-ridden city, 70 miles west of Baghdad, where many areas are so dangerous that they go unpatrolled.