The village head of Darbaguda in Kalimela area was returning home along with his wife from a nearby forest when the explosive device planted by Maoists on the road went off, Malkangiri Superintendent of Police Akhileswar Singh said.
While Bira Padiami (50) died in the blast, his critically injured wife was taken to the nearby hospital by the villagers for treatment, Singh said.
Police said the ultras were believed to have planted the explosive device, probably a pressure bomb, targeting the security personnel as a BSF camp is located near the site.
Maoists observe "martyrs" week from July 28 to August 3 every year to pay tribute to their leaders and cadres who lost their lives.
Normal life was affected to some extent in rural pockets of Malkangiri district as passenger buses and other vehicles stopped plying since yesterday at many places fearing trouble, police said adding shops and business establishments also remained closed in areas like Kalimela, Padia and Motu.