A senior Iraqi army intelligence officer and three bodyguards have been killed in a suicide bombing near the northern city of Mosul.

Two bombers attacked the home of Brigadier-General Awni Ali, the director of the defence ministry's intelligence school, in Tal Afar town.

A local official said one suicide bomber was killed by guards, but when the general and his bodyguards went outside, a second suicide bomber detonated his explosives.

Iraq has seen an increase in suicide bombings since the start of the year.

Sunni Islamist insurgents tied to al-Qaeda are trying to ignite the kind of sectarian violence that pushed the country close to civil war in 2006-2007.