A mother suspected of suffering from a mental illness allegedly killed her 14-year-old son in her rented room in Choam Chao III commune, in the capital’s Por Sen Chey district, police said on Monday.

Theng Kosal, Choam Chao III commune police chief, said the woman had two sons, the younger of which was at school at the time of the incident. He said neighbours heard a loud argument at about 8am between the suspect and the elder son but it got quiet minutes later.

Kosal said soon after this, the suspect walked out of the room, locked the door, left the key with a neighbour – to whom she told she had killed her son – and then went to report the matter to police.

She told police she clubbed her son with a pestle and slashed him with a cleaver. She said she got angry after her son attacked her. Kosal said police immediately arrested her.

However, he said police aren’t fully convinced the woman suffers from mental illness. “We suspect she has mental problems, which is why she killed her son. However, she does not have documents confirming any mental illness and appeared normal during interrogation,” Kosal said.