Violence is down across Iraq from its peak in 2006 and 2007, , but attacks remain common [Reuters]

A series of bomb attacks and shootings across Iraq has killed at least 12 people, including six security force members, and wounded 87 others, medical and security officials said.

In the deadliest attack on Thursday, a vehicle packed with explosives detonated near a police station in the town of Al-Gharma, just west of Baghdad in the Sunni Anbar province.

Four policemen were killed and six others wounded in the blast, according to Omar Belli, a doctor at the main hospital in the nearby town of Fallujah.

Belli said that another bomb explosion in Fallujah left seven people wounded, four of them police.

Meanwhile, a car bomb that exploded in the southern port city of Basra near a mosque on Thursday evening as worshippers were leaving  killed three people and injured 50  others, according to a doctor at the city's Al-Sadr hospital.

In the town of Al-Qaim on the Syrian border, a roadside bomb against a convoy carrying Iraqi army Major General Ismail Shahab killed a convoy driver and wounded two of Shahab's bodyguards, according to a military official who did not want to be named. It was unclear if Shahab was hurt.

In the capital, meanwhile, a magnetic "sticky bomb" attached to a car in the Al-Amriyah neighbourhood of west Baghdad killed the vehicle's driver and wounded two others, an interior ministry official said.

A car bomb near Palestine Street in east Baghdad detonated as an army patrol was passing by, killing a civilian bystander and injuring 15 others, including 11 soldiers, the official said, speaking on condition of anonymity.

Gunmen attacked a police checkpoint in Hama, also in the capital's east, on Thursday, killing one policeman, while a roadside bomb in the central neighbourhood of Allawi wounded five people, according to the official.

And in the main northern city of Mosul, an Iraqi soldier was killed by a bomb blast at an army checkpoint, said a military officer who did not want to be identified.

Thursday's violence comes after Al-Qaeda's front group in Iraq threatened a campaign of 100 attacks, starting mid-August, to avenge the death of Osama bin Laden in a US special forces raid in Pakistan nearly four months ago.

Violence is down across Iraq from its peak in 2006 and 2007, but attacks remain common. A total of 259 people were killed in violence in Iraq in July, according to official figures, the second-highest figure in 2011.