LAGOS, Nigeria - Security forces raided five villages in Nigeria's oil-rich southern delta, leaving 15 people dead and homes ransacked and burned, residents and militant leaders said Thursday. The security forces said the raids were part of an effort to combat attacks on multinational oil operations in the Niger Delta. Troops in speedboats with mounted machine guns raided the villages of Sunny Zion, Idegbagbene, Odiogbogbene, Opia and Ogbinbiri between Sunday and Wednesday, said Maj. Said Hamed, spokesman for the region's 3,000-strong military-police task force. He was unable to confirm whether anyone was killed in what he described as a "cordon-and-search"...