It happened on Wednesday evening. The cause of the crash is not yet known, but a spokesman says the aircraft was supporting ground troops against militants in the Damasak area which borders Niger.

The Nigerian military has recently intensified air and ground operations in the region in response to an upsurge in deadly attacks by Boko Haram and fighters loyal to the Islamic State group - mainly targeting military positions.

Dozens of Nigerian soldiers have been killed and their weapons seized in such attacks in recent months.Earlier on Tuesday, the Nigerian Air Force said it killed a number of fighters from the Islamic State West Africa Province - a Boko Haram splinter group - when it targeted their meeting venue near the town of Baga.

Security is a key campaign issue as Nigeria gears up for presidential and parliamentary elections in February.