Sustained heavy gunfire and loud explosions have been heard in Niger near the international airport outside the capital, Niamey.

Multiple eyewitness accounts and videos showed air defence systems apparently engaging unidentified projectiles in the early hours of Thursday.

The situation later calmed down, reports say, with an official reportedly saying the situation was now under control, without elaborating.

It is not clear what caused the blasts, or if there were any casualties. There has been no official statement from the military government.

The gunfire and blasts began shortly after midnight, according to residents of a neighbourhood near the Diori Hamani International Airport, the AFP news agency reports. They said calm returned after two hours.

The airport houses an air force base and is located about 10km (six miles) from the presidential palace. 

One local resident told the BBC that shots had been fired from outside the airport, targeting planes.

Others described their fear as they heard the gunshots and explosions.

“We didn't sleep last night," said one resident. "Our room and the whole house was shaking from the gunshots and explosions,” she said.

"Yesterday was the first time I have ever heard gunfire," another woman said. "We were so scared."

Several unconfirmed reports said unknown assailants had thrown explosive devices towards the airport area before exchanging fire with security forces.

According to the FlightRadar24 website, several flights bound for Niamey have been diverted.

AFP reports there was a heavy security deployment around the airport on Thursday morning.

Niger is led by Abdourahamane Tiani who seized power in a 2023 coup that ousted the country's elected civilian president.

Like its neighbours Burkina Faso and Mali, the country has been fighting jihadists who have carried out deadly attacks across the region.

Early on Thursday morning, supporters of the military government took to the streets of Niamey ⁠to show their support for the authorities.

The country is a major producer of uranium.

A huge uranium shipment destined for export has been stuck at the airport amid unresolved legal and diplomatic complications with France after the military government nationalised the country's uranium mines.

"The situation is under control. There is no need to worry," the Anadolu news agency quoted a foreign affairs ministry official as saying, without elaborating.

The official told the agency they were trying to determine whether the gunfire was linked to the uranium shipment.