Gunfire and explosions were heard on Saturday morning in Niger's capital, Niamey, including around a military base near the city's airport, which has been attacked twice this year by suspected terrorists.

The origins of Saturday's shooting were not immediately clear and authorities made no official comment.

"There is heavy gunfire and explosions at Base 101 in Niamey," one local resident told AFP, a report confirmed by several other witnesses.

The first shots were heard at about 1:00 am local time (0000 GMT) and continued until daybreak, according to a video published by a local journalist filming the area around the airport.

Another resident in the west of Niamey said he heard sporadic small arms fire at about 5:00 am.

Security deployment

Several social media posts also reported shooting and explosions in the city, particularly in the administrative area where the presidential palace and national television station are located.

There were no immediate reports of casualties.

Videos online showed armoured vehicles deployed to reinforce the neighbourhood near the airport.

Air Force Base 101, located within the international airport complex, notably houses the headquarters of Niamey's Russian Africa Corps partners, as well as the command of the unified force of the Alliance of Sahel States, of which Niger is a member with Burkina Faso and Mali.

Airport targeted in the past

The site is sensitive. Between December and January, it hosted a large shipment of uranium concentrate, which was held up while awaiting export. No movement of the shipment has been identified since.

Niamey airport has been targeted twice this year, in January and June, by terrorists linked to Daesh and Al-Qaeda.

Twenty assailants were killed and four soldiers wounded in the January assault, authorities said at the time.

In June, at least 11 soldiers and two civilians were killed, as well as 22 attackers, according to the defence ministry. Both attacks were repelled by the army.

The terrorists are also active in neighbouring Burkina Faso and Mali, both allies of Niger.