India Maoists 'threaten' to kill policemen
Maoist rebels in India have threatened to kill four policemen they took hostage last week unless Maoist prisoners are freed, officials say.
They abducted seven policemen in Bijapur, Chhattisgarh state, on 19 September. Three of them were found dead in forest two days later.
Indian security forces have been battling Maoists in several states.
This month, Maoist rebels released three policemen they had held hostage for eight days in northern Bihar state.
They abducted the policemen after a gunfight in which seven other officers were killed.
The rebels say they are fighting for the rights of the poor and the landless.
Last year, the Indian government launched a major offensive against the Maoists in several states. The insurgency is seen as the country's biggest internal security challenge.