Seven employees of a French mineral and water drilling firm and a local official were killed early Thursday when gunmen attacked their site in southeastern Niger, the company said.

‘A group of terrorists attacked the building where a team of Foraco drillers and technicians were resting in the village of Toumour, in southeastern Niger,’ the company said in a statement.

‘The assailants opened fire on the sleeping personnel and killed eight people,’ it said, adding that five others were wounded, two seriously.

The victims, all Nigerien, were drilling two water wells to supply a camp for displaced people at a refugee camp at Toumour, near the borders with Chad and Nigeria.

Foraco, based near the southern French city of Marseille, said the site had been chosen in conjunction with the Niger armed forces escort protecting the workers.

The company did not identify the attackers, but Toumour was the site of a fierce firefight in September 2016 between the military and Boko Haram which left 38 of the insurgents dead.

‘We know that Boko Haram is active in the region but for now we've had no claim of responsibility, neither official or unofficial,’ Thierry Merle, Foraco's vice president in charge of Europe and the Middle East, told AFP.

‘We've been operating in Niger for 20 years, and at this site since a month ago,’ Merle said.

‘We hadn't received any threat in particular,’ he added, and the company had not previously suffered similar attacks.

Boko Haram fighters have carried out a series of attacks in northeast Nigeria in recent days, the latest in a nine-year insurgency in the country which has driven 1.8 million people from their homes.

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