U.S. forces fought off an attack in the early hours of the morning Monday against a military base, killing five of the assailants, in a neighborhood that was once a notorious Shiite militia stronghold.

The attackers opened fire on the joint U.S.-Iraqi security station at 1:20 a.m. in the eastern district of New Baghdad, the U.S. military statement reported. The soldiers returned fire, killing at least five of the assailants.

"Coalition soldiers will continue to use deadly force to defend themselves when attacked by militants and extremists," said Maj. Joey Sullinger, spokesman for the 4th Brigade Combat Team, 10th Mountain Division.

Hours later, a roadside exploded in the same district, tearing through a minibus and killing three civilians and wounding six others, Iraqi police said. The U.S. military set the toll at only two dead.

The former Shiite militia stronghold saw fierce clashes between U.S.-Iraqi forces and extremists earlier this year. But such brazen attacks have been relatively rare since anti-U.S. cleric Muqtada al-Sadr declared a cease-fire.

Elsewhere in the country, there was a rash of so-called "sticky bomb" attacks in which militants target certain individuals by attaching explosives to their vehicles.

One of the bombs struck a car carrying a doctor and his friend as they left his clinic near the Khillani Square in central Baghdad. The two men were killed and seven other people were wounded, police said.

Another bomb hidden under the car of a director-general in the Trade Ministry exploded in the garage of a hospital he was visiting, seriously wounding the official and a civilian, according to police and hospital officials.

In northern Iraq, a bomb stuck to a car in Tuz Khormato exploded, killing an Iraqi soldier who was driving, an official at the local hospital said.

The Iraqi officials spoke on condition of anonymity because they weren't authorized to release the information.