At least seven security personnel including an army major and a police inspector were killed and four were wounded in a Maoist guerrilla ambush in Parbat district west of Kathmandu Wednesday, the state run Nepal Television reported. It quoted security sources as saying a 30-minute gun battle between the security forces and the Maoists erupted after the initial explosion. Two civilians - a taxi driver and a passenger - were missing following the clash. The television report said the injured were undergoing treatment at Kushma, the headquarters of Parbat district.The television also reported that the Maoists abducted over 500 students and teachers from various schools from eastern villages of the far-western Kanchanpur district Wednesday. Local radio reports said the Maoists abducted the students and teachers to involve them in indoctrination sessions.