Ministry of Defence says 11 soldiers, 2 civilians and 22 attackers killed in Diori Hamani International Airport assault.

An attack by armed men on an airport in Niger’s capital has killed 11 soldiers and two civilians, according to the country’s defence ministry, five months after a major assault.

Twenty-two armed attackers were also killed in the assault and about 20 suspects were apprehended, the ministry added in a press statement read out on national television on Thursday.

Soldiers in Niamey fought suspected rebels around the Diori Hamani International Airport and a military airbase on Thursday, sources told Al Jazeera earlier in the day.

A source said gunmen affiliated with an armed group attacked at approximately 6:00am (05:00 GMT) local time.

One airport employee who lives near the airport told Al Jazeera he heard heavy exchanges of gunfire and saw a large military deployment as he drove towards work and decided to turn back for safety. A second local source living close to the airport also reported hearing intense artillery.

A source told the AFP news agency that gunmen had arrived at a security checkpoint near the airport “by taxi”, then encountered “fierce resistance” from security forces. Gunfire rang out for hours in the area.

A “large-scale operation” by the army “is underway and the international airport, which is fully secured, remains open to air traffic,” the defence ministry statement said.

The situation appeared mostly calm by noon (11:00 GMT), with only sporadic ⁠fire possibly linked to the army’s sweeping operations, a Reuters news agency witness and two residents said.

There was no immediate claim of responsibility for the attack, which the defence ministry said left four people wounded, according to a preliminary toll.

The airport and military airbase ‌are in the same complex, with the base situated opposite the civilian terminal.

The ISIL affiliate in the region claimed responsibility for an attack on the complex in January. Twenty fighters were killed and four soldiers wounded in the January 29 assault, authorities said.

At the time, the group said it had targeted air command headquarters and drone assets and claimed to have “delivered a direct blow” to the Sahel country’s anti-rebels operations.

In recent weeks, the authorities have started tearing down thousands of illegally built homes next to the airport in what they said were efforts to counter a “terrorist” risk.

They alleged the shantytowns had been infiltrated by armed rebels. The airport perimeter fence has been extended, and more than 350 security cameras have been installed inside and outside the perimeter.

Niamey’s airport is one of the country’s most strategic military sites. It hosts the G5 Sahel “counterterrorism” force, Russian forces and the drone unit carrying out strikes against rebel groups.

Uranium stocks that Niger is seeking to sell are also stored at the airport. Any strike on those facilities could pose a serious environmental risk.

Niger, like its Sahel neighbours Mali and Burkina Faso, has struggled to contain attacks from armed groups linked ⁠to al-Qaeda and ISIL that have killed thousands and displaced millions ⁠across the three countries.