The eastern Indian state of West Bengal is on high alert a day after a senior Maoist rebel leader was killed in a gunbattle there.

Koteswar Rao, known as Kishenji, was reportedly shot dead Thursday during a gunbattle in a forest in the West Midnapore district. He was wanted for the killing of at least two dozen police officers in an ambush on a security camp, along with other attacks.

Authorities on Friday ordered extra security throughout West Bengal for fear of retaliatory action by Maoist rebels.

Security forces were also dispatched to the area where Rao was killed to search for other rebels who had escaped.

Meanwhile, some Indian politicians claimed that the Maoist commander was not killed in a gunbattle but instead in a “fake” police encounter.

On Thursday, Indian Home Secretary R.K. Singh said Rao's killing is a “huge setback” for the Maoists, noting that he was number three in the rebel group's hierarchy.

Maoist rebels, known as Naxalites or Naxals, have infiltrated more than 20 Indian states.

Indian leaders have referred to Naxalism as the country's biggest internal security threat. The groups include some of the country's most extreme poor, who say they are struggling against state-sanctioned acquisition of their land and natural resources.

Thousands of civilian and police deaths in India are blamed on Naxal attacks since the groups emerged in the late 1960s.