The incident took place at the junction of Geyland Rd and Engku Aman Rd at about 8.56pm.
An eyewitness says he heard a siren and saw the traffic police patrol car chasing another car.
Seconds later, he heard a loud bang and saw that the traffic police patrol car had crashed into a BMW car.
The vehicle that the cops were chasing after escaped.
The SCDF was activated and one man in his 30s was sent to Changi General Hospital.