A car bomb and suicide bomber killed at least 16 people and injured at least 30 Thursday in Tikrit, police said, marking the deadliest attack in Iraq in about three weeks and coming days before the start of the Muslim holy month of Ramadan.

A car bomb detonated about 11 a.m. outside the state-run Rafidain Bank in Tikrit, about 90 miles north of Baghdad, according to local police officials. The blast killed a police officer and at least seven members of the Iraqi army’s 4th Brigade who were collecting their monthly paychecks, the officials said.

Moments after the explosion, as a crowd gathered and ambulances and other emergency vehicles arrived, a suicide bomber wearing a police uniform detonated another bomb, police said.

Most of those killed or injured by the blasts were police officers or members of the Iraqi military, and most were Kurdish, according to the local police.

Tikrit was the home town of Iraqi leader Saddam Hussein, who was captured by U.S. forces in late 2003 and executed by the U.S.-backed Iraqi government three years later.

No group immediately asserted responsibility for the attack, but the method used — one explosion followed by another as a crowd gathers — resembled those of previous assaults by al-Qaeda in Iraq. Local gangs are also known to be targeting banks across Iraq, leading many financial institutions to install blast walls and take other security precautions.

Police officials in Tikrit said authorities had expressed concern Wednesday that the Rafidain Bank was distributing paychecks to Iraqi service members outside the bank’s blast walls.

Violence has dipped this month across Iraq after a string of attacks on local police and government buildings at the start of July. Rocket attacks on U.S. military installations and Baghdad’s Green Zone are still common; a rocket hit the Green Zone on Wednesday, but there were no reports of injuries.

So far this month, five U.S. service members have either died or been killed in action in Iraq, according to iCasualties.org.

Special correspondents Asaad Majeed in Baghdad and Muhanned Saif Aldin and Othman Mohammed in Tikrit contributed to this report.