The rebels have 22,000 combatants, and have spread to more than 180 of the country's 630 districts from just 56 in 2001, according to the government and a new report this week by the Institute for Conflict Management (IFCM), a New Delhi 'think-tank' .
"The security threats are changing and it's bigger than ever before as more and more areas are coming under their command. It is not a happy sight at all," B.K. Ponwar, head of the Counter Terrorism and Jungle Warfare College in India, told Reuters.
"We must address the barrel of the gun of the Maoists, or in two years the issue will get out of hand."
Prime Minister Manmohan Singh has described the Maoist rise as one of the gravest threats to India's internal security, and the insurgency is shaping up as an issue ahead of a general election due by May.
The main opposition says the ruling Congress party does not have a strategy to counter the Maoists and that police are poorly armed.
Police and intelligence officials say the Maoists are now recruiting hundreds of poor villagers to bolster their ranks, and are equipped with automatic weapons, shoulder rocket launchers, mines and explosives.
The rebels say they are fighting for the rights of the farmers and the poor who make up the majority of India's 1.1 billion population.
They regularly attack rail lines and factories, aiming to cripple economic activity over a large area.
India's says the Maoists are making their presence felt in 22 of the country's 29 states. Thousands of people have been killed since the uprising began in the late 1960s.
In the last week, rebels have launched attacks in areas previously unaffected by fighting. In the western state of Maharashtra, rebels shot dead 15 police, while in Bihar's they killed 10 police.
More than 1,000 cases of Maoist attacks were recorded last year in which more than 200 police personnel killed.
"The rebels now have the capability to launch simultaneous attacks and they have the firepower. But the Indian government does not seem to have the capacity to neutralise them," Ajai Sahni of the Institute for Conflict Management said.
Police efforts are hampered by lack of manpower and weapons as well as poor coordination between states, meaning rebels can escape pursuit by crossing state lines.