A 16-year-old boy is suspected by police of having shot and killed his mother and younger brother before turning the gun on himself at their home in Trang on Monday.
The bodies were discovered late Monday morning.
Police found three people dead with gunshot wounds in a bedroom on the second floor of the house. The bodies of the mother and her young son, 14, were discovered in a bed. Her elder son, 16, died with a significant gunshot wound to his face and one hand holding a gun.
Police did not identify the dead family members.
According to investigators, the woman worked as the manager of a local bank branch.
The staff rang her husband to ask where she was. The husband then rang his wife's sister, who went to the family home to check on her.
The woman's sister rang the doorbell but there was no answer. The husband and neighbours broke into the house, where they found the three bodies.
Police said the 16-year-old son appeared to have shot his mother and young brother before turning the gun on himself.
