Three Naxalites, one of them carrying a reward of Rs 5 lakh, were killed in an encounter with security forces in Chhattisgarh's Bijapur district on Saturday morning, the police said.

It was the first encounter in the state after Union home minister Amit Shah last week appealed to the Naxalites to lay down arms and join the mainstream.

A gunfight broke out on a forested hill in the Indravati National Park area around 9 am on Saturday when a joint team of security personnel was out on an anti-Naxalite operation, Inspector General of Police (IG), Bastar Range Sundarraj P said.

Personnel of the District Reserve Guard (DRG) units of the police from Bijapur and Dantewada districts, Special Task Force (STF) and the 202nd and 210th battalions of CoBRA (Commando Battalion for Resolute Action, an elite unit of the CRPF) were involved in the operation, the official said.

The bodies of three Naxalites were recovered from the spot afterwards, he said.

A 12 bore rifle, single-shot rifle and some other weapons and explosives were also seized, the IG added.

Of the three slain Maoist cadres, one was identified as Anil Punem, an area committee member and commander of Matwada LOS (local organisation squad), he said, adding that Punem carried a reward of Rs 5 lakh on his head.

Punem was allegedly the mastermind of the blast carried out by the Maoists near Ambeli village in Bijapur in January, Sundarraj said.

On January 6, Naxalites blew up a vehicle using an Improvised Explosive Device (IED) weighing 60 to 70 kg, killing eight security personnel and their civilian driver near Ambeli village.

The identity of the other two cadres was yet to be ascertained, the official said.

With the latest operation, 138 Naxalites have been killed in separate encounters in the state so far this year. Of them, 122 were eliminated in the Bastar division which includes seven districts including Bijapur.

Speaking in Dantewada on April 5, Union minister Shah had said Naxalites were "our own people" and no one felt happy when they were killed. They should surrender and join the mainstream, he had said while asserting that the government was committed to end the Naxal menace.