A car bomb at the entrance to an Iraqi army base as potential new recruits were massed at the gate killed at least 25 people on Tuesday, security and medical officials said.
The blast struck at around midday (0900 GMT) in the town of Taji, 25 kilometres (15 miles) north of Baghdad, an interior ministry official and a medic said. Both spoke on condition of anonymity.
It was not immediately clear how many of the victims were soldiers or new recruits. Differing tolls and breakdowns of casualty figures are common in the chaotic aftermath of violence in Iraq.
The blast struck as the base was holding a recruitment day to welcome potential new soldiers, events which have been frequent targets of militants intent on carrying out mass-casualty attacks in the past.
Tuesday's bombing was the deadliest single attack to hit Iraq since July 24, when a series of coordinated blasts also in Taji killed 42 people.