The owner of the squatter house, who lives there with his wife and two children, said the two men also lived in the home.
District police chief Assistant Commissioner M Chandra said the murdered teen was related to the house owner's family but had no relation with the suspect. It was understood that both the teen and the suspect usually sleep in the living room.
“Around 11.30pm, the houseowner woke up from his sleep when he heard noises.
"Upon coming out of his bedroom, he saw the suspect holding a knife while the victim was lying bloodied at the kitchen area next to the living room,” said Chandra.
With the help of neighbours, the houseowner managed to restrain the suspect.
The victim's remains have been sent to the Queen Elizabeth Hospital forensic department for post mortem examination. Police are still investigating the motive.