Suspected jihadists have launched an attack on the international airport outside Niger's capital Niamey.

Niger's defence ministry said four military personnel were injured and 20 attackers were killed, with state television saying that a French national was among them.

There were 11 arrests over the attack at Diori Hamani International Airport overnight from Wednesday to Thursday, in which sustained heavy gunfire and loud explosions were heard nearby.

On Friday, the Islamic State group, through its Amaq information service, said it was behind the "co-ordinated surprise attack" targeting "the military base" of the Niger army.

No casualty figures were given but Amaq said the assault had caused "major damage".

Eyewitness accounts and videos showed air defence systems apparently engaging unidentified projectiles in the early hours of Thursday but services at the airport returned to normal during the day.

The head of Niger's junta on Thursday thanked Russia for its help in foiling the attack on the airport, and accused the presidents of France, Benin and Ivory Coast of backing those responsible. 

He did not give details of what help Russia had provided, or provide any evidence to support his accusations against the other countries.

The military which seized power in a July 2023 coup have frosty relations with France and Benin, and regularly accuse them of trying to destabilise Niger, which both countries deny. 

"We commend all the defence and security forces... as well as Russian partners who defended their security sector with professionalism," General Abdourahamane Tiani said on state radio.

"We remind the sponsors of these mercenaries, notably Emmanuel Macron, Patrice Talon and Alassane Ouattara: we've heard them bark quite enough; now they should get ready to listen to us."

Since the coup, Niger's junta has cut military ties with France, the former colonial power, and instead worked with Russia to help tackle the Islamist fighters who have been fighting in the region for over a decade.

Niger's Defence Minister Salifou Modi said in a statement on public television that the mercenaries attacked an air base in the capital for "about 30 minutes" before an "air and ground response".

The channel broadcast footage of Tiani visiting the military base, showing the bodies of the attackers and said there was "a Frenchman" among them.

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

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 were diverted.

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

Niger 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 shipment was unharmed in the attack, according to sources cited by Reuters news agency.