Libya's rival government conducts air strikes on Islamic State in Sirte - official

TRIPOLI (Reuters) - Military aircraft belonging to a rival Libyan government on Thursday attacked Islamic State positions in and around the central city of Sirte, where the radical group claimed to have seized an air base, a government official said.

Islamic State has exploited the general turmoil and security vacuum in Libya to build up a presence in several cities, where two governments are vying for power four years after the ousting of Muammar Gaddafi.