LAGOS, June 21 (Reuters) - Nigerian troops killed 12 militants and rescued some hostages in a dawn raid on an Italian-operated oil facility in the Niger Delta on Thursday, the army said. Italian oil giant Eni <ENI.MI> had said that 16 Nigerian oil workers and 11 soldiers were being held hostage at the Ogbainbiri flow station since Sunday, but the army said they found only 11 oil workers there.
