Nigeria's military says it killed 37 suspected Boko Haram militants in a ground and air attack that began late Monday on an encampment in a remote area of the country's embattled northeast.
A military spokesman said the assault occurred in Borno state. He said arms and ammunition were recovered at the site, and that several vehicles and motorcycles belonging to the Islamist group were destroyed.
The military strike came two days after witnesses said heavily armed Boko Haram fighters dressed as Nigerian soldiers ambushed and killed 19 people at a fake checkpoint in a nearby village near the Cameroon border. Witnesses and survivors told Western news agencies that most of the victims were hacked to death.
Boko Haram Islamists have been fighting since 2009 to impose a strict form of Islamic law in Nigeria's Muslim-majority north.
The militants have been blamed for thousands of deaths, and they continue to launch attacks in the region despite an all-out military offensive ordered by Nigerian President Goodluck Jonathan in May.
Analysts say the government offensive has driven the militants deep into the countryside, where they appear to be regaining strength.