Gunmen and suicide bombers staged an ambitious assault on a government building in Baghdad, officials said, killing two people in the latest such attack in the Iraqi capital by militants trying to further undermine the Shiite-led government’s shaky authority.

The firefight at a state-run transportation company was one of several attacks that left 11 dead across the city, and it came as Iraq grapples with a stubborn insurgency in the country’s western Anbar province. Government troops are battling to oust al-Qaeda-linked fighters and their allies from cities in the area.

At least six gunmen were involved in Thursday’s main attack, according to Interior Ministry spokesman Saad Maan Ibrahim, who said the assailants stormed the state-run Company for Transportation on Baghdad’s Canal Street, where many government offices are located.

The police shot and killed four of the militants inside the building, while the other two blew themselves up at the entrance, Maan said. He also said that at least one employee and a policeman were killed.

There was no immediate claim of responsibility for the day’s attacks. But coordinated assaults targeting Shiites, security forces and government buildings are frequently the work of al-Qaeda’s affiliate in Iraq, which has been emboldened by the successes of its fellow militants in the civil war next door in Syria and by widespread Sunni anger at the Shiite-led government.

Civilians inspect the aftermath of a car bomb attack near the al-Farasha pastry shop in the southeastern district of New Baghdad, Iraq, Thursday, Jan. 30, 2014. Car bombs and a shooting, mainly in Shiite areas, killed and wounded scores of people in the Iraqi capital on Wednesday, officials said, as authorities released a rare photograph of a man they say is the leader of al-Qaida’s local branch. Since late December, members of Iraq’s al-Qaida branch have taken over parts of Ramadi, capital of the largely Sunni province of Anbar. They also control the center of the nearby city of Fallujah. Government forces and allied tribes have been trying to wrest control back from the militants. (Khalid Mohammed/Associated Press)

Last year, insurgents — some of them suicide bombers — unleashed a large and carefully planned assault on the Iraqi Justice Ministry that included car bombs and gunmen disguised as police, killing at least 24 people.

Also Thursday, a parked car bomb ripped through a market in Baghdad’s northern Kasra neighborhood, killing at least four people, officials said. Another car bomb exploded at a bus station in Baghdad’s eastern Ur neighborhood, killing five civilians.

The bombings in Baghdad occurred as Iraqi security forces and allied tribal militia fight to recapture parts of the Anbar provincial capital, Ramadi, and the city center of nearby Fallujah from al-Qaeda-linked rebels and other groups. Clashes continued Thursday, with state TV saying that at least 24 militants were killed.

At night, gunmen abducted three brothers of Sabah Karhout, the head of Anbar provincial council, councilman Faleh al-Issawi said.

The gunmen blew up Karhout’s house in Karmha, near Fallujah, before taking the brothers away. Issawi said Karhout was in the house during the attack.

— Associated Press