March 22 (Reuters) - Indian Prime Minister Manmohan Singh has called the country's Maoist, or Naxalite, insurgency the biggest internal security challenge facing India since independence. Here are five facts on the three-decade-old armed struggle: * Ideologically led by activist Charu Majumdar, killed in police action in early 1970s, the ultra-left rebels began their fight with an armed peasant revolt in West Bengal's eastern Naxalbari village on May 25, 1967, which was brutally crushed by the state government. * Starting out poorly armed with spears and bows and arrows, the Maoists have acquired guns, hand grenades and guerrilla war expertise over the years. Thought to number up to 20,000, they say they are fighting for the rights of poor farmers and landless labourers. * Some 749 people, including 285 civilians, were killed in the conflict in 2006, according to the Asian Centre for Human Rights. More than 3,000 have been killed in the insurgency between 2002-2006, analysts at Global Security estimate. * At least 13 of India's 29 states have Maoists operating in them. The insurgency now affects 172 of the India's 602 districts. * The creation in 2005 of a government-backed group, the Salwa Judum (Campaign for Peace), in Chhattisgarh -- one of India's poorest states, where tens of thousands have been displaced by the rebel violence -- has been criticised by human rights activists for aggravating the conflict. Source: Reuters, Global Security (www.globalsecurity.org/military/world/war/naxalite.htm), The Asian Centre for Human Rights' Naxal Conflict Monitor (www.achrweb.org/ncm/ncm.htm)
