Samarahan district police chief DSP Lee Chong Chern said the woman was believed to have committed suicide after killing the boys aged seven and four by hanging herself in the toilet of the house.

Neighbours had sensed something amiss as the house was too quiet. They alerted the police, which then deployed a team to check on the occupants.

“Police received a call from the public at 7.55pm after neighbours sensed something amiss as the house was too quiet.

“Upon inspecting the house, police found two children in a bedroom. The area around their mouths had darkened, suggesting poisoning,” Lee said.

“The seven-year-old was already lifeless while the four-year-old was in critical condition but died while being rushed to the Kota Samarahan Heart Centre,” he said.

Lee said there was also an opened bottle of Clorox in the bedroom where the children were found.

“The case is being investigated as sudden death,” he said.