Maoist guerrillas triggered a landmine explosion in India's central state of Chhattisgarh on Friday killing 15 policemen, news reports said, according to dpa. The policemen were travelling in a vehicle when the ambush took place in a jungle in the Bijapur district, which is considered a stronghold of Maoist insurgency in the country. "Maoists triggered a landmine explosion near Pamed police station in the district, in which 15 policemen were killed," Girdhari Nayak, the inspector general in charge of anti-Maoist operations told the IANS news agency. Officials said information about the attack was coming in slowly, since the blast took place in a remote area, some 560 kilometres from the state capital Raipur. Maoist rebels operating in 13 of India's 29 states, are most active in states like Chhattisgarh, eastern Jharkhand and southern Andhra Pradesh, and claim to fight for the rights of the rural poor and tribal people. According to New Delhi-based Asian Centre for Human Rights (ACHR) at least 384 people, including 129 civilians, 162 security forces personnel and 93 Maoist rebels have been killed between January and September 2007. Chhattisgarh is the state worst-affected by the Maoist violence, accounting for more than 200 deaths in the conflict.