An eight-year-old boy was murdered and his 13-year-old sister and mother were found with severe head injuries in their house at Vellamputhur near Thirukovilur in Villupuram district on Thursday.
The police gave the name of the victim as Samayan, son of Aarayi, 50, a widow.
The police said Aarayi was staying in the house with her son and daughter Dhanam while three other sons and a daughter were working in Bengaluru.
The crime came to light when neighbours found the door of the house open.
Battling for life
They found Samayan murdered while Aarayi and Dhanam were battling for life in their house. The local people immediately alerted the police and rushed them to the Thirukovilur Government Hospital.
Aarayi and Dhanam were later referred to the Government Medical College and Hospital at Mundiyambakkam.
The police have detained one person for questioning in this connection.
