He had just bathed his three-year-old son on Tuesday evening when he looked up and saw an alarming sight - a swarm of bees nesting in a corner of the bathroom wall, close to the ceiling.
The sales manager, who wanted to be known only as Mr Hong, said this was the first time he had seen something like this since the family moved into the ninth-storey flat in Block 602, Yishun Street 61, three years ago.
Mr Hong quickly took his son out and closed the bathroom door.
"I tried to be as quiet as possible to avoid disturbing the bees," he told The New Paper on Friday.
The bees had flown in through the bathroom window. The bathroom is attached to the master bedroom.
The bees stretched from a corner of the window all the way to the ceiling.
Mr Hong contacted the Nee Soon Town Council as his wife took the three-year old boy and their other son, who is a year old, to the living room.
Mr Hong was told that pest controllers would be called in to handle the problem.
While waiting for them to arrive, he went back to the bathroom and took photographs of the bees.
"I thought it was quite unusual and posted the photos on Facebook. Some friends told me to be careful. One said it was a good sign as the word for bee in Mandarin sounds like the word for wealth."
When the pest control technician arrived around midnight, he placed an auto-release canister of pesticide inside the bathroom and closed the door.
Within 15 minutes, dead bees were all over the bathroom - on the floor and toilet seat cover and in the sink.
Mr Hong said: "I felt quite sad to see all the bees dead, but there was no choice as they could have harmed someone."
He hosed down the bathroom and used a plastic broom to sweep the dead bees into a plastic bag.
"I had to move around carefully... There were thousands of them and they almost filled the plastic bag," said Mr Hong.
He took two hours to clean the bathroom as the pesticide had left an oily residue.
Don't try to kill the bees yourself
The bees could have been looking for a new nesting site after their nest was disturbed, said a manager at pest control company Clean Solutions.
Mr Azlam Shah, 33, said: "Bees are attracted to light and areas that are cool."
He said it is not common for bees to cluster indoors. Clean Solutions encounters an average of two or three cases a year.
Residents who encounter swarms of bees in their homes should leave the affected room, close the door and get a pest controllers to get rid of the bees.
Mr Azlam said: "Do not disturb the swarm and do not try and kill the bees on your own such as spraying pesticide at them. They may attack you."
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