Six persons, including three security personnel were killed by armed Maoists in separate incidents in Orissa, Bihar and West Bengal today in fresh attacks. <br/><br/>The Maoists blew up a government toll plaza in Gaya district in Bihar using dynamites and looted 16 weapons. They snatched three lakh rupees in cash from the plaza counters. Two persons including a security guard and a truck driver were killed in the attack.<br/><br/>The violence occured as the Maoist' 48-hour bandh in seven states to protest against the Government's operations against Naxals drew to a close.<br/><br/>In Orissa, three security personnel were killed and six injured, four of them critically, in a fierce encounter with Maoists in Gajapati district early today.<br/><br/>Acting on a tip-off about the movement of ultras, a team of security personnel including the elite anti-naxal Special Operation Group and state police launched a combing operation in Ambajari forest in the wee hours.<br/>In the exchange of fire, three jawans were killed and six others injured, four of them critically.<br/> <br/>In another incident in the nearby Malkangiri district,Maoists blew up a pump house and control room near the pipeline of a private industrial house meant for movement of minerals in Chitrakonda area.<br/>Police said about 50 armed ultras raided the area in the early hours and triggered an explosion after overpowering and assaulting the guards present at the site.<br/> <br/> In West Bengal, Maoists killed a CPI(M) activist, after abducting him from home in West Midnapore district. His bullet-riddled body was recovered from the area today.