Four Central Reserve Police Force (CRPF) jawans lost their lives in an encounter with Naxals in the poll-bound district Bijapur of Chhattisgarh on Saturday.
Two jawans sustained injuries after Naxals blew up the anti-landmine vehicle.
The incident occurred around 4 pm near Murdanda camp of the CRPF under Awapalli police station, when its 168th battalion was out on "area domination" operation, Bijapur Superintendent of Police Mohit Garg was quoted as saying by PTI.
When the MPV carrying six personnel was around one km away from the camp, ultras triggered a powerful landmine blast, he said.
Reinforcement was rushed to the spot immediately and the injured personnel were being evacuated. Security officials are not retrieving the bodies from the site.
The attack took place on a day when Chief Minister Raman Singh launched the ruling BJP's campaign for the first phase of polls on November 12 in neighbouring Sukma district.
The first phase of election will cover 18 constituencies in eight Naxal-affected districts - Bastar, Kanker, Sukma, Bijapur, Dantewada, Narayanpur, Kondagaon and Rajnandgaon.
Naxals had recently put up posters in parts of Bastar region calling for boycott of the polls.