They saw smoke spewing out of the windows of a fifth-storey flat and decided to investigate.
When they got there, they realised there was a fire in the flat's kitchen.
To their shock, an elderly man inside the unit appeared oblivious to the fire.
Mr Rahizam AB Rahim, 46, told The New Paper yesterday: "My brother-in-law and I rushed to the flat and we saw the uncle sitting on the floor by the gate.
"He was trapped inside and all I could think of was getting him out of there.
"I asked him, 'Uncle, are you okay? Please open the gate. I've come here to help you. Can you give me the padlock key and I'll help you open the gate.'"
But the man, who was in his 60s, mumbled something incoherent and remained on the floor, leaving Mr Rahizam at a loss over what to do next. The incident happened on Sunday at around 1.50pm at Block 116, Jalan Bukit Merah, when Mr Rahizam, a technical assistant, was about to leave for a wedding.
The father of eight was at the carpark with his brother-in-law. He was waiting for his wife and kids to come down when they saw thick, black smoke coming out of the kitchen window of a unit on the same floor as his. They decided to check it out.
"When we stepped out of the lift, a crowd of people had gathered near the unit, but they didn't dare go up to the gate.
"When I got to the gate, I could see flames coming out from the kitchen."
Just as Mr Rahizam was contemplating how to get the elderly man to safety, a neighbour stepped forward with a bolt cutter.
Mr Rahizam tried to cut the padlock with the bolt cutter but found it too difficult. He eventually used the cutter to break the aluminium windows and grilles to allow another neighbour to climb inside to help the man.
But the resident refused to leave the flat through the window.
The neighbour then got out of the flat as the heat was getting intolerable and he had burned one of his hands, Mr Rahizam said.
"The uncle was very stubborn. He was covered in sweat and mumbling to himself," he said.
"I told him again to give me his flat keys and this time, he walked slowly to a room and came out holding a pair of jeans.
"At first, I was worried that he was going to lock himself in the room, but luckily he didn't."
The elderly man rummaged through the pockets of the pair of jeans and finally produced the keys.
Mr Rahizam asked him for the keys and he complied.
"The fire was so intense that I couldn't touch the padlock on the gate with my bare hands. One of the neighbours passed me a T-shirt to hold the padlock," he said.
After Mr Rahizam opened the gate, he helped the man out and sat him down while another neighbour got him a glass of water.
By then, firefighters had arrived and quickly put out the fire.
Mr Rahizam said that when he moved into his flat four years ago, the man was already living there.
WIFE NOT HOME
Neighbours said the man lives with his wife, but she was not home at the time of the fire.
A housewife, Mrs Russell Santiago, 41, who lives next door to the man's flat, told TNP that she was cooking lunch when she smelled smoke.
"I thought it was nothing. It didn't occur to me that it was a fire until I heard an explosion," she said.
When she looked out of her window, she saw residents in the opposite block and people at the carpark below pointing to the unit next to hers.
To her horror, she saw fumes coming out from her neighbour's kitchen window and promptly left the flat with her husband and two sons.
A Singapore Civil Defence Force (SCDF) spokesman said it was alerted to the fire involving the contents of a kitchen at 1.50pm. SCDF officers put it out using two compressed air foam backpacks and a water jet.
The cause of the fire is under investigation.
This article was first published on April 19, 2016.
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