In the latest in a string of skirmishes between the army and militias in northern Niger the airport in the city of Agadez was attacked on Sunday evening, but aid agencies working in the region say they are not considering pulling out.

“It’s really business as usual,” said Jeff Ratcliffe, head of the Irish Red Cross in Agadez, which had one of its vehicles stolen at gunpoint last month. “We will continue to work in the areas south of Agadez, but will not go north or east because there is a problem with bandits.”

Michael Flachaire, head of mission for Action Against Hunger (AAH) in Niger, said: “We take events like this very seriously, considering that we lost 17 international staff in Sri Lanka last year. We will analyse the security situation this week, but for now, AAH will remain. When the time comes that we feel as though our personnel are in danger, we will pull out of northern Niger.”

A UN staff member in Niamey confirmed that UN agencies working in the region have not oulled out, although stricter security measures and curfews have been enforced.

Witnesses in Agadez said 20 armed men in jeeps and on motorcycles briefly fought with soldiers outside the airport in Agadez at around 7.30pm on Sunday evening.

The Nigerien Movement for Justice (MNJ), a rebel group that in interviews with IRIN has accused the central government in Niamey of neglecting the northern region and failing to develop the country, claimed responsibility for Sunday’s attack at the airport.

The MNJ, which is led by remnants of a rebel group dating back to the 1990s dominated by ethnic Touaregs, claims to have led four assaults on the Nigerien military since it launched its campaign in February. It has also been accused of laying mines in the region of Iferouane, to the north of Agadez.

The government denies that there is a rebellion in the north and blames the recent attacks on bandits and criminals smuggling drugs and arms through the vast desert region.

The governor of Agadez Abba Malam Boukar banned travel between towns in northern Niger last week. He also imposed a curfew in Agadez to be enforced by the army.