At least 12 soldiers have been killed and 12 others were wounded in an attack on a military base in a restive area of northern Iraq.
Thursday's attack took place at the base outside the city of Mosul, about 360 kilometres northwest of Baghdad, when a suicide bomber detonated his explosives-laden truck at the gates of the facility, an army officer and a police officer told the AP news agency.
A group of gunmen then opened fire from apparently commandeered military Humvees, sparking a shoot-out.
A medical official confirmed the causality figures. All officials spoke on condition of anonymity because they are not authorised to talk to media.
Over the past months, Mosul and the surrounding region have seen bold attacks by fighters, mainly from an al-Qaeda-splinter group known as the Islamic State of Iraq and the Levant (ISIL), against military and security forces.
Four people have been killed in latest artillery fire in the Iraqi town of Fallujah in Anbar Province, medical sources have informed Al Jazeera.
The ISIL has seized control of parts of Anbar's provincial capital, Ramadi, since December, as well as the centre of the nearby city of Fallujah.
Since then, Iraqi government security forces and allied Sunni tribal fighters have been struggling to dislodge ISIL members.
In Baghdad, the Iraqi capital, at least nine people were killed on Thursday after a car bomb exploded in the crowded commercial area of Karrada, police officials told Al Jazeera.
No one immediately claimed responsibility for Thursday's attacks.
Violence has escalated in Iraq over the past year, with 2013 seeing the highest death toll since the worst sectarian bloodletting in 2007, according to United Nations figures. More than 8,800 people were killed in violence last year.
The escalation in violence comes in a crucial time, as Iraqis prepare to hold parliamentary elections on April 30, the first such vote since US forces left Iraq in 2011.
Authorities recently said there would be no balloting in parts of Anbar province where clashes are under way and which are not deemed safe.