PATNA - Fourteen Maoist insurgents were killed Saturday in a pre-dawn gun battle between two rebel groups in eastern India . It was the latest clash between factions of the ultra-leftist group. “We strongly feel that it was a revenge attack to prove supremacy,” Anurag Gupta, a senior officer of Jharkhand police, told AFP. Police said Maoists gunned down members of a rival group in Palamu district of the mineral rich state of Jharkhand.