Musul, Iraq ? A bomb-laden car plowed through a razor wire fence and exploded Saturday outside a police station in the north of the country, killing nine Iraqis and injuring 45, including policemen there to pick up their pay.

It was unclear if the attack was a suicide bombing or the driver fled before the explosion. U.S. officials have said recent vehicle bombings and suicide attacks in Iraq bear the mark of al-Qaida.

In a separate incident, three U.S. soldiers from the 4th Infantry Division were killed Saturday in a roadside bombing near the northern oil center of Kirkuk. Their deaths brought to 522 the number of American service members who have died since the Iraq war began March 20.

Also Saturday, a bomb exploded under the car of police Col. Adnan Radeef al-Ani in front of his house in Baghdad, slightly injuring five children in the street. Al-Ani told The Associated Press the bomb apparently was triggered by a timer but no one was in the vehicle when it exploded.

Witnesses in Mosul, 225 miles north of Baghdad, said what appeared to be a suicide attacker drove through a security barricade in front of the police station before blowing up his vehicle. Iraqi officials confirmed a car bomb but were unsure if the driver detonated the explosive from inside or parked and fled.

Saturday was a pay day and the station was crowded with staff at the time of the midmorning bombing, said police Lt. Mohammed Fadil. Five of the dead were police and the others were Iraqi civilians, policeman Khalid Ahmed said.

Severed limbs, some of them smoldering, and decapitated bodies littered the bloodied street after the attack, the sixth major vehicle bombing in Iraq in the past two weeks but the first in Mosul, the country’s third-largest city and the principal metropolis in the north.

The blast gouged a huge crater in the street and shattered windows of nearby buildings. Pieces of burning car wreckage spewed acrid, black smoke.

At least five cars were destroyed.

Mosul police look at the front end of the car they suspected carried the explosives at the scene of a car bombing outside an Iraqi police station in downtown Mosul, Iraq. Officials said nine people, including civilians and policemen, were killed and 45 were injured in the blast Saturday .

Stunned survivors stumbled in the street, their clothing soaked in blood. U.S. soldiers hurried to the scene and cordoned the area. No U.S. troops were near at the time of the blast.

Saturday’s attacks occurred a day before the start of the four-day Eid al-Adha, or Feast of Sacrifice. The feast, a major Muslim holiday, commemorates the Quran’s account of God allowing the patriarch Abraham to sacrifice a sheep instead of his son Ismail.

The Old Testament account says another son, Isaac, was spared.