In this file photo dated Oct 1, 2020, a Nigerian Air force helicopter fly a Nigerian 60th anniversary banner at the Aso-Rock in Abuja, Nigeria during the country's 60th Independence Celebration. (PHOTO / AFP)

ABUJA — A Nigerian Air Force helicopter crashed in the north-central Nigerian state of Niger on Monday, with sources saying it had come under fire from armed bandits.

The helicopter crashed near Chukuba village in the Shiroro local government area of the state, air force spokesperson Air Commodore Edward Gabkwet said.

Niger state lies hundreds of kilometres southeast of Niamey, the capital of the country of Niger where a junta seized power in a coup last month

An investigation was under way, he said. It was not known how many people were on board.

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Niger state lies hundreds of kilometres southeast of Niamey, the capital of the country of Niger where a junta seized power in a coup last month.

Two military sources said bandits fired at the helicopter which had been sent to evacuate victims of an attack on Sunday that killed at least 10 soldiers caught up in an ambush.

Armed gangs are rife across Nigeria's northwest where they rob and kidnap for ransom. Thousands of people have been killed in attacks in recent years.

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Islamist group Boko Haram is also active in northern Nigeria alongside the Islamic State of West Africa, a regional affiliate of Islamic State.