A person allegedly hacked six members of a family, including an infant, to death and later surrendered to the police at a village in Visakhapatnam district early on Thursday.
City Commissioner of Police Manish Kumar Sinha visited Juttada village under Andhra Pradesh's Pendurthi mandal to take stock of the situation.
Police told news agency Press Trust of India that Battina Appala Raju attacked the family members of Bammidi Ramana with a large sickle, allegedly owing to an ongoing battle between the two families for some time now.
"What triggered the incident is not clear yet. We are investigating whether it was old rivalry or an extra-marital affair that led to the killings," a senior police official said.
Besides Ramana, his family members Usharani (35), Allu Ramadevi (53), N Aruna (37), Usharani's children Uday (2) and Urvisha (6 months) were killed, the police told news news agency Press Trust of India.
Appala Raju later went to the Pendurthi police station and surrendered, reported Press Trust of India.
The bodies have been sent for a forensic test while police were questioning Raju to establish facts in the case.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)