(Photo: CGTN)

Armed men killed eight people on Thursday in a late night attack on French drilling company Foraco's water well site in southeastern Niger, Foraco said.

"Last night at 2 a.m. local time, a group of terrorists attacked the small building where a Foraco team was sleeping and killed seven of them, plus one civil servant," the company said in a statement.

Five other employees were wounded, with two in serious condition, it said. The workers were drilling two deep water wells for the water ministry in southeastern Niger's Diffa region.

A security source says that the assailants were believed to belong to Nigerian jihadist group Boko Haram, which is active near the border with Nigeria.

Boko Haram has been trying since 2009 to establish an Islamic state in northeast Nigeria and has launched repeated attacks into neighboring Niger, Chad and Cameroon. Thousands of civilians have died in the violence.