The victims, Rahasingh Munda alias Bira (39) and his mother Mukta Munda (60) of Mundatoli in the Chandiposh police station, were hacked to death on December 5 in their house by the accused, they said.
Two youths of the same locality, Sanika Munda alias Temp (30), his wife Sumitra and their friend, Sudarshan Munda (32) first attacked Bira with an axe, killing him on the spot, police said adding the killers then hacked Mukta, who was cooking, before fleeing.
The police seized a mobile phone, photo identity card and the three axes used in the crime, SDPO Amaresh Panda said.
It is learnt that Temp lost his two-year-old child two years back and he believed that it was due to witchcraft by Bira and his mother,