The incident has sparked protests in the area over the safety of Dalits
A Dalit man and his parents were shot dead in Madhya Pradesh allegedly by neighbours who had accused him of harassing the wife of one of the attackers, the police said.
The incident was reported from Devran village of Damoh district on Tuesday morning.
An argument broke out between the two families on Monday evening after the wife of the main accused, Jagdish Patel, alleged that Manak Ahirwar stalked her and often stared at her, police said.
The argument, however, was seemingly resolved after some villagers intervened.
The next morning, a furious Jagdish Patel, along with five other men from his family, again went to Manak Ahirwar's home, this time with weapons, officials said.
A heated argument between the families escalated and the armed men fired at 30-year-old Manak, his parents and his younger brother.
While Manak and the elderly couple died on the spot, his brother Mahesh Ahirwar is being treated at the hospital.
DR Teniwar, Superintendent of Police, Damoh said Jagdish Patel has been arrested and a search is on for five more, who are missing.
"The entire incident allegedly happened over harassment of a woman from the Patel family," Mr Teniwar said.
He said a case has been registered on a complaint filed by Mahesh Ahirwar listing charges of murder, attempt to murder and under a stringent law on crimes against Scheduled Castes and Scheduled Tribes.
The killings have sparked protests in the area over the safety of Dalits in Madhya Pradesh.