BAGHDAD (Reuters) - At least 24 people were killed in bomb explosions in the Iraqi capital late on Monday, including blasts near two Shi'ite Muslim mosques and at a busy bus station, police and medics said.

No group immediately claimed responsibility for any of the attacks, but Shi'ites are often targeted by Sunni Islamist insurgents who have been regaining ground in Iraq over the past year and overran several towns in recent weeks.

In Monday's deadliest attack, a minibus packed with explosives blew up at a bus station in the mainly Shi'ite district of Ur in northern Baghdad, killing at least 11 people, police and medical sources said.

"The parked minibus inside the garage raised suspicions and when drivers started shouting for its driver, it exploded," said bus driver Farah Abbas. "Many people were thrown back by the blast and vehicles caught fire".

A further nine people were killed in car bomb attacks targeting mosques in Baghdad's predominantly Shi'ite districts of Amil and Karrada, police and medical sources said.

A car bomb near a busy street in Baghdad's western district of Ghazaliya killed four others. In separate incidents in the city of Tikrit, gunmen shot dead a police colonel and a barber inside his shop.

The army on Monday was fighting to wrest control of Sulaiman Pek from Sunni militants who took over parts of the northern town last Thurdsay and raised the black flag of the Islamic state in Iraq and the Levant (ISIL) over it.

ISIL is active in the civil war in neighbouring Syria and is also present in the city of Falluja, which has been under siege by the army since January 1, when militants took over.

(Reporting by Kareem Raheem; additional reporting by Ghazwan Hassan and Ahmed Rasheed; Writing by Isabel Coles; Editing by Tom Heneghan)