The humanitarian aid organisation ACTED  is to lodge a criminal complaint to clarirify the circumstances around the murder of a group of its employees in Niger on Sunday.

Six French nationals died along with their Nigerien guide and driver, about six kilometres from the town of Kouré, in a wildlife reserve about an hour's drive southeast of the capital, Niamey.

Troops in Niger backed by French air support have launched a hunt for the killers of the eight people, while French anti-terrorism prosecutors have formally opened an investigation.

Frédéric de Saint-Sernin, Chief Operating Officer of ACTED told a press conference in Paris that where the team were killed was considered one of the safer places in the west African country:  

"If you look at the map, of course you say well, these are red zones and it is a dreadful paradox that our young humanitarians died in this yellow zone, a zone where we could go, I would say in a fairly normal way, when we needed a rest."

The organisation's co-founder, Frederic Roussel, told reporters in Paris that the international community had to do more to ensure the protection of humanitarian workers: 

"The international community must understand the contradiction between asking us to support these populations who live under the most dramatic circumstances and leaving us alone against violence, where we are the easiest targets."

An ambulance sent by the French military stationed in Niger found the bodies along with their burned-out vehicle.

The team of eight - four men and four women - were killed shortly before midday on Sunday in a giraffe park which is considered one of the safer places in the west African country. The attackers are believfed to have arrived on motorcycles, travelling through the bush and then waited for the group's arrival. 

In a tweet, Niger's President Issoufou Mahamdou described the attack as cowardly and barbaric and extended his sincere condolences to the families of all the victims: 

One of the biggest French NGOs, ACTED has been present in Niger since 2010 and provides aid to displaced people and local populations who are particularly vulnerable due to conflicts in the region as well as through lack of food and droughts.