(Adds French foreign ministry confirmation, background) ABUJA, Aug 3 (Reuters) - Gunmen have kidnapped two French expatriates near Nigeria's oil industry hub of Port Harcourt in the restive Niger Delta, military and security sources said on Sunday. More than a dozen gunmen late on Saturday ambushed patrons at a local bar in Onne in Rivers state and exchanged fire with navy personnel, resulting in at least three deaths, a security source said. The French Foreign Ministry confirmed two of its citizens were kidnapped. Lieutenant-Colonel Sagir Musa, army spokesman for Rivers state, said it was not yet clear who the two French expatriates worked for. Insecurity in Nigeria, the world's eighth-largest oil exporter, has cut crude output by around a fifth since militants launched a campaign of sabotage in early 2006 to press for greater development in their neglected communities. Criminal gangs have taken advantage of the breakdown in law and order, frequently kidnapping businessmen, local politicians and foreign workers for ransom. More than 200 foreigners have been seized in the Niger Delta, the heart of the country's oil sector, since early 2006. Almost all have been released unharmed. Last month, two Germans working for Nigeria's largest construction firm, Julius Berger, were kidnapped, prompting the company to suspend operations in the delta. (Reporting by Randy Fabi in Abuja and Estelle Shirbon in Paris; Editing by Tume Ahemba)
REFILE - UPDATING CAPTION A file photo taken in April 2008 shows Berge Sisar, a liquefied petroleum gas (LPG) tanker from which gunmen kidnapped eight foreign oil workers off Nigeria's Niger ...