(Reuters) -

A wave of suicide bomb attacks on security personnel and government buildings killed at least 12 people across Iraq on Sunday, police said.

In what appeared to be coordinated strikes, bombers, some driving cars packed with explosives, attacked sites in the town of Rawa, 260 km (160 miles) northwest of Baghdad. Another bomber hit a busy street in the northern city of Samarra.

No one claimed responsibility for the blasts, though Sunni Muslim insurgents, including al Qaeda, have regularly targeted security personnel and others working for the Shi'ite-led government.

One attacker drove a car up to a checkpoint on the main road into Rawa and blew himself up, officers told Reuters. Another targeted a police station and a third the house of the mayor, seriously wounding him and killing at least three others.

Two other suicide bombers wearing police uniforms set off their explosive vests inside Rawa's local council building, killing three people including the organization's deputy head, police said.

A series of attacks on Rawa last month was claimed by the Islamic State of Iraq and the Levant, which was formed earlier this year in a merger between al Qaeda's Iraqi and Syrian affiliates.

Around 7,000 people have been killed in acts of violence so far in 2013, reversing a decline in sectarian bloodshed that since it last climaxed in 2006-07.

A suicide bomber blew himself up near the house of a senior policeman on the southern outskirts of Samarra, 100 km north of Baghdad, police told Reuters.

The attacker drove up to a group of people who had gathered at the scene of an earlier, smaller explosion close to the house of senior police officer Nasser Dawood, added.

A suicide bomber in a car drove up to a group of people who had gathered at the scene of an earlier, smaller explosion close to the house of senior officer Nasser Dawood.

He was away when the bomber set off his explosive, but most of those killed and wounded in the blast were members of his family, the force said.

Al Qaeda's Iraqi affiliate was forced underground in 2007 but has since regrouped, invigorated by the war in Syria and growing resentment of the government that came to power after the U.S.-led invasion in 2003.

The militants have accused the government of marginalizing their minority sect since the overthrow of Sunni strongman Saddam Hussein.

Hardline Sunnis regard Shi'ites as apostates.

(Reporting by Ghazwan Hassan in Sammara, Kamal Na'ama in Ramadi, writing by Suadad al-Salhy; Editing by Andrew Heavens)