Three members of a family were found dead at Doddanayakana Koplu near Arakalgud on Sunday evening.
The deceased have been identified as Krishna (55), his wife Nanjamma (50), and daughter Bhoomika (22).
The police, who got to know about the deaths after a neighbour informed them, suspect that the victims committed suicide by taking poison at home on Sunday.
The relatives claim the victims could have taken the extreme step after the recent arrest of Lokesh, the son of Krishna, in connection with a murder in the village.
Nagaraj, a youth of the village, was found murdered in the village on August 6 and the police had taken Lokesh into custody for interrogation.
Arakalgud Police have registered the case and are investigating.
People in distress or having suicidal tendencies can seek counseling by calling Karnataka's suicide prevention helpline 104.
