A 24-year-old person was hacked to death by an unidentified armed group at Danketiya in Tangalle yesterday night.
Police said that the Parents and a brother of the victim were also critically injured in the attack.
They are receiving treatment at the ICU of the Karapitiya hospital.
The injured were identified as a 54-year-old Cooperative officer, a 50-year-old school teacher and their son.
Police believe the attack has led upto suspicions of a theft of gold jewellery.
Tangalle Police said no suspect has been arrested as yet.