SINGAPORE - A man was found dead at the foot of a Housing Board block in Pasir Ris on Sunday (Aug 20), and a woman believed to be his daughter was later found lying motionless in a flat in the same block.

The police told The Straits Times that they were alerted to a case of unnatural death at Block 560, Pasir Ris Street 51, at 1.30pm on Sunday.

A 70-year-old man was found lying motionless at the foot of the block. Investigations led to the finding of a 27-year-old woman in the same state in a flat on the second floor.

They were both pronounced dead by paramedics at the scene.

ST understands that the woman was the man's younger daughter and had special needs. She was found with multiple stab wounds.

When ST arrived on the scene, a Caucasian man was seen exiting the unit at 11.45pm with a bag in hand and pulling a yellow luggage bag behind him.

He is the son-in-law of the 70-year-old man, according to a neighbour, and is married to the older daughter. The dead man also has a third child - a son.

According to neighbours, eight people live in the flat - the 70-year-old man, his wife, their three kids, the son-in-law, and two grandchildren.

A neighbour who lives two doors from the pair who died said he heard a loud sound and thought someone had thrown furniture down.

The 58-year-old who gave his name only as Mr Azman said: "He was already lying on the floor... I thought why this man was lying on the ground... he had a big cut on his right leg. At first I thought maybe he was drunk or had fainted."

Mr Azman said the man had a vertical cut from the knee to the shin.

His wife, who gave her name as Madam Faridah, said she had seen the 27-year-old woman throw tantrums when she first moved in four years ago.

"After around seven months, she changed a lot and didn't scream or throw tantrums any more," said the housewife.

She added that she has never heard the man shout at his daughter in a harsh voice before.

Members of a family who live three units away but declined to be named said the man, who had a part-time job and enjoyed swimming, was well-known around the block as he was friendly.

They reacted in shock when they realised what happened. They last saw the man a week ago, when he offered an unused fish tank to them knowing that they reared fish.

Police investigations are ongoing.

Additional reporting by Fabian Koh