At least 13 Maoist insurgents were killed in a clash in central India, police said Wednesday, taking the rebel toll in the long-running conflict to 50 this year.

Police said the gunfight with security forces took place in a remote forest in Chhattisgarh state's Bijapur district on Tuesday.

Local police chief P. Sundarraj said officers had seized a large cache of rifles, machine guns and ammunition.

"The identity of the Maoist dead bodies is yet to be established," Sundarraj said, adding that three of those killed were women.

More than 50 Maoists have been killed in India this year, 46 of them in Chhattisgarh and another four in Maharashtra state, according to police figures.

India has deployed tens of thousands of security personnel to battle the Maoist rebels across the insurgent-dominated "Red Corridor", which stretches across central, southern and eastern states but has been shrinking in size.

The insurgents, who are known as Naxalites and say they are fighting for the rural poor, have carried out guerilla attacks since 1967.

New Delhi has pumped millions of dollars into infrastructure development into remote areas, and claims to have confined the insurgency to 45 districts in 2023, down from 96 in 2010.

The annual number of rebels killed has dropped by more than two-thirds in the past decade, according to government figures.

India is to hold marathon six-week-long general elections beginning on April 19.