Pest control worker Tan Kui Seng, 68, went to the Chua Chu Kang Lian Sing Keng temple in Teck Whye Lane early yesterday morning to unlock the gates as usual.
But he got a shock when he saw a 2m trail of blood outside the prayer hall, with a body lying motionless on the ground.
"I also saw a large pool of blood and I got frightened. I immediately ran to the coffee shop nearby and told someone to call for an ambulance," said Mr Tan.
Paramedics at the scene pronounced Mr Tan Poh Huat, 53, dead at 7.09am. It is understood that he had sustained a head injury.
The police have classified the case as an unnatural death and are investigating. Foul play has not yet been ruled out.
The dead man, who was divorced and unemployed, had been living in the temple for the past five years, said Mr Tan, who is on the temple's executive committee.
"Most of us at the temple knew him well and he had a good personality. He usually woke up quite early, around 4am, and I would see him at the coffee shop when I made my daily rounds in the morning,"said Mr Tan, who last saw him about a week ago.
He added that the dead man, whom he last saw about a week ago, was known to have kidney problems and was receiving dialysis treatment and social assistance.
"But he was quite independent - if he felt unwell because of his kidney problems, he would call for the ambulance himself so that he could be taken to the hospital."
The temple is usually locked from 10.30pm to 7am. There were no signs of trespass on Saturday night, said Mr Tan.
The dead man's sister, Madam Tan Sui Kee, 60, a part-time sales worker, said he was not known to have been involved in any disputes. He leaves three children.