A hit-and-run driver who left a motorcyclist and his pillion rider injured by the road was caught by a group of cyclists taking part in their regular ride.
The group, called PG/SK Riders, saw the man and woman lying on a patch of grass outside Changi Airbase (West) with debris from the crash strewn nearby.
The pack of 35 to 40 riders called for police and an ambulance and split themselves into groups, with some attending to the injured couple, some setting off to find the rogue motorist and others directing traffic.
"We saw the motorcycle about 500m away and a car in front at a red light. The guys blocked him from moving," said Mr Paul Goh, 34, who started the cycling group 2 1/2 years ago.
"The entire front bumper was gone, it was obvious it was him."
The cyclists surrounded the Honda Airwave driver, seized his keys and held onto them until police arrived.
Meanwhile, someone alerted the nearby airbase, and medics from the Singapore Armed Forces (SAF) attended to the victims.
The motorcyclist suffered a cut to his forehead and was taken to Changi General Hospital along with his unconscious passenger. Both are said to be in their 20s.
The police said that the driver has been arrested.
Mr Goh, who works in sales, said the group rides almost every day and that Tuesday night's incident was not the first time they had helped someone in need.
About a month ago, they assisted a man who had suffered a heart attack. He had fallen to the ground and was not responding to questions.
In a separate case about three hours later, a motorist who knocked down a cyclist on Upper East Coast Road and fled the scene was also arrested.
Chinese evening daily Shin Min reported that a taxi driver who saw what happened called the police and tailed the BMW driver for about an hour until he was nabbed at Lorong 30, Geylang Road.