Two French oil workers were kidnapped Sunday in Nigeria’s southern oil region, French officials said.

A statement released by France’s Foreign Ministry confirmed that two French nationals had been kidnapped but did not provide additional details about the two or say for which company they worked.

A crisis group has been established, and French officials in Nigeria are working to win the workers’ freedom “as quickly as possible,” the statement said. It said French embassy officials in Lagos are in contact with the hostages’ employer.

The spokesman of the military unit charged with calming the Niger Delta, Lt. Col. Sagir Musa, said the two expatriates were seized overnight from a bar in the town of Onne.

More than 200 foreigners have been kidnapped in two years of increased violence across Nigeria’s southern oil region. Hostages are generally released unharmed after a ransom is paid, although several have died in botched snatches or rescue attempts.