Police and paramilitary soldiers were searching on Monday for remaining insurgents after their ambush left a large number of the Maoist fighters dead.

The assault took place after authorities received a tip that anywhere from 30 to 60 rebels were meeting in a forest near the border of Odisha and Andhra Pradesh states, in southeastern India.

The ensuing gunfight left at least 21 rebels dead and two policemen wounded. Among the dead were a top Maoist leader and his son, the Press Trust of India reported.

Authorities said they had also uncovered four AK-47s and three self-loading rifles at the scene. As of early Monday morning, the remaining rebels had scattered into the forests, and police had formed a search party to find them.

Decades-long insurgency

The incident is one of the deadliest in the ongoing insurgency, which began in the 1960s. The rebels, who say they are inspired by Chinese revolutionary leader Mao Zedong, claim to be fighting on behalf of poor tribal groups, who have been deprived of land, jobs and other rights by the government.

The rebels have a presence in at least 20 Indian states, but are most active in the heavily forested states of Chhattisgarh, Odisha, Bihar, Jharkhand and Maharashtra. More than 7,000 people have lost their lives in the fighting between 2005 and 2016 alone.

In June, security forces killed at least 12 Maoists at one of their strongholds in Jharkhand. That incident followed a deadly attack on the police in March, when suspected rebels triggered a landmine blast in Chhattisgarh, killing seven policemen.

Prime Minister Narendra Modi has faced pressure to stop the insurgency, which has been described by former Prime Minister Manmohan Singh as the country's most pressing internal security threat.

blc/kl  (AFP, dpa, AP)