ABUJA, Sept 14 (Reuters) - U.S. oil major Chevron <CVX.N> confirmed one of its oil platforms in Nigeria was attacked by militants on Sunday, but production was already shut down due to previous pipeline problems, a company official said. "There was an attack on a platform already shut down due to pipeline problems," the official, who did not wish to be named, told Reuters. The Movement for the Emancipation of the Niger Delta on Sunday declared an "oil war" in southern Nigeria and said it already attacked oil flow stations and pipelines, including a Chevron platform in Kula. (Reporting by Randy Fabi)
