He used to sleep at the void deck
There was always a stench from his neighbour's flat a few doors away.
But last month, the 66-year-old cleaner, who wanted to be known as Mr Yap, noticed that the smell was different.
After he failed to see his neighbour for a week, he felt something was amiss and called the police.
Mr Yap's hunch was right. The decomposing body of his neighbour, known to him only as Din, was found in the three-room flat on Nov 18.
A spokesman for the Singapore Civil Defence Force said the man was in his 50s.
The door to his flat was unlocked so no force was required to enter the flat.
Neighbours said the dead man, who used to work as a postman, was often seen sleeping at the void deck of the block.
A retiree who wanted to be known as Mr Tay, 62, said that every morning when he walked his dog, he would see Din sleeping on a bench.
He said: "He was big-sized and he wore many gold chains on his neck. He slept at the void deck every day and I didn't know he lived just upstairs.
"Once I even saw him peeing in the bushes (beside the void deck)."
Another retiree, Mr Yeo Sou Hai, 70, who has lived a few doors away from the flat for about 20 years, said his neighbour had been living alone after his mother died more than 10 years ago.
"His door was always closed and I've never seen any relatives. He was always sleeping downstairs, maybe because he couldn't stand the smell too," he added.
Mr Yap, who also knew Din for more than 20 years, said there had been a putrid smell from the flat for more than 10 years.
"Whenever I spoke to Din, I had to keep a distance (from him) because his (body odour) was very strong," he added.
"I brought the issue up with my MP (Member of Parliament) more than 10 years ago and his neighbours had also been complaining for a long time. If only something had been done sooner."