11/29/2013 03:12 EST | Updated 01/29/2014 05:59 EST

Coquitlam Hit And Run Witness Sought

COQUITLAM, B.C. - Mounties in Coquitlam, B.C., are looking for a witness who had the forethought to use a rock and the sidewalk to write down the licence plate number of a suspect vehicle.

RCMP Sgt. Barb Thornborough says the man witnessed the fatal hit-and-run crash Wednesday afternoon and scratched the information on the sidewalk before leaving.

The RCMP say an elderly couple was hit by a grey truck making a turn onto a local road.

Seventy-six-year-old Juan Jose Rosales and his 66-year-old wife Marta Dolores Rosales were both killed.

Police say the truck driver fled the scene, but officers later arrested a male suspect and located a vehicle.

Drugs and alcohol have been ruled out as factors in the incident, and anyone with information is asked to contact the police.