At least 11 people were killed and 23 others injured on Saturday in three back-to-back suicide attacks north of the Iraqi capital Baghdad, police said.
The attacks started with the detonation of a suicide car bomb targeting a checkpoint in the city of Tikrit, around 170 kilometres north of Baghdad.
Shortly afterwards, two suicide bombers riding motorcycles rigged with explosives blew themselves up in the same place, police said, adding that the casualties included security personnel and civilians.
The bombings were carried out shortly after a convoy carrying local police chief, Damin al-Jabouri, and head of a provincial security committee, Jassem Jabara, passed through the checkpoint, police said.
The two officials were not harmed.
Local authorities imposed a curfew in Tirkrit following the attacks, Iraqi website Alsumaria news reported, citing an unnamed security official.
“The curfew is in place until further notice. We have got information that there are other suicide bombers inside the city," the official said.
No one has claimed responsibility for the attacks.
In April last year, Iraqi forces, backed by a US-led air alliance, regained Tikrit from the Islamic State extremist militia.
Iraq is gearing up for a long-awaited campaign to dislodge Islamic State from its stronghold in Mosul, the country’s second-largest city.