Among the deceased are an elderly couple and their son. The incident took place at Kamalpur in Tripura’s Dhalai district on Thursday.
Police officials said that a fight broke out between members of the two families over a land dispute in which seven people were injured.
The deceased have been identified as Rajani Das (70 years), his wife Bilasi, (67 years) and their son Pratyus Das (41 years).
Rajani Das passed away while being rushed to the Agartala Government Medical College and Hospital in Agartala, while his wife and son died in the morning on Friday, police informed.
Meanwhile, the others who were injured in the scuffle are undergoing treatment at the district hospital in Dhalai.
Police have also detained two people for questioning in connection with the incident.