The retiree had just pushed her shopping cart across the road when she heard a loud crash.
Madam Tey Kah Git, 66, turned around and saw that a car had knocked into two boys who, just seconds ago, were walking behind her.
The accident happened in front of Block 401 at Tampines Avenue 7 at 10.10am on Sunday.
One of the boys fell at the black Mitsubishi’s front right wheel. The other was thrown into the air by the impact and landed face-down about a metre away.
A witness, who wanted to be known only as Mr Tan, told The New Paper that the driver helped the boy who was lying face-down to the grass patch at the road divider. The other boy got up on his own.
Mr Tan said the driver then allegedly got back into his car and drove away.
Police later arrested the driver, a 33-year-old man, at his home in Tampines within three hours of the incident.