At least 29 people have been killed and 42 more wounded by suicide bombers who attacked two police stations and a hospital in a city northeast of the Iraqi capital Baghdad.

Captain Ghalib al-Karkhi said the bombings in the mixed Shia-Sunni Baquba targeted the provincial headquarters, the Iraqi army and a hospital.

One attacker drove an explosives-packed car to the headquarters of a police rapid reaction force in Baquba, the capital of Diyala province.

A second suicide car bomb went off at a police checkpoint while the third went off at Baquba general hospital.

The attacks come in a tense run-up to a parliamentary election slated for March 7.