Five Naxalites were killed in an encounter with security personnel in Chhattisgarh's Narayanpur district on Tuesday, police said.

The gunfight took place in a forest under Kohkameta police station area in Abujhmad, a hilly forest area when a joint team of personnel from different security forces was out on an anti-Naxal operation, a senior police official said.

"Five Naxalites have been killed in the action so far. The search operation is still underway in the area and further details are awaited," he said, adding that security personnel were reported to be safe.

The operation, involving personnel of the District Reserve Guard, Special Task Force, Border Security Force and the Indo-Tibetan Border Police from different districts, was launched on Sunday, police said.

With the latest incident, the number of Naxalites killed so far this year in separate encounters with security forces in the state has risen to 138. While 136 Maoists were gunned down in the Bastar division, comprising seven districts including Narayanpur, two others were killed in Dhamtari district under the Raipur division.

On June 15, eight Naxalites and a Jawan of the Special Task Force (STF) were killed in an encounter in Narayanpur district.

Six Naxalites were gunned down in an encounter in Narayanpur on June 5 and seven Naxals were killed on the Narayanpur-Bijapur border on May 23.

At least 12 Naxalites were killed in an encounter in Bijapur on May 10, while 10 cadres, including three women, were gunned down along the border of Narayanpur and Kanker districts on April 30.

On April 16, 29 Naxalites were gunned down in an encounter with security forces in Kanker district, officials said.

(With Inputs From Agencies)