BAGHDAD - Iraqi police have arrested 30 members of an al-Qaeda cell, including the alleged mastermind of truck bombings last week that killed 17 people in the former insurgent stronghold of Fallujah, officials said yesterday.

Tariq al-Karbouli, the alleged leader of the cell, was picked up Monday in the Abu Ghraib area west of Baghdad, Iraqi officials said.

The other members of the cell were apprehended in a series of raids that ended early yesterday, the officials added.

They spoke on condition of anonymity because they were not authorized to release the information.

Two bomb-laden trucks exploded Thursday at police stations in Fallujah, 40 miles west of Baghdad, killing 17 people and leveling buildings, police reported.

The brazen attacks in the most heavily guarded city in Iraq raised questions about the ability of Iraqi forces to ensure security as the United States scales down its combat role under the newly ratified U.S.-Iraqi pact, which calls for an American pullout within three years.

One of the Iraqi officials said that Karbouli, who works for a government-owned yogurt company, said explosives used in the attacks were smuggled into the city over a period of time hidden under bananas and other foodstuffs.

The official said that Karbouli had confessed to his role in the bombings but that the 11 other people directly involved were still at large.

Fallujah is in Anbar province, the mostly Sunni area of western Iraq that was the main theater of the war until Sunni tribes there broke with al-Qaeda last year and joined forces with the Americans.

The city has been under intense security since U.S. forces drove out al-Qaeda and other Sunni extremists in November 2004 during the fiercest urban fighting of the war.

With a drop in violence, the United States transferred security control of the province to the Iraqis in September.