Vancouver police are warning the public about two targeted muggings in which patrons leaving the River Rock Casino were followed and robbed at gunpoint.

The first incident took place on May 24 around 2:00 a.m. and the second on June 9 at 1:30 a.m.

The victims of both robberies saw a dark-coloured SUV behind them flashing a blue light after leaving the casino in Richmond, Const. Lindsey Houghton told ctvbc.ca.

Believing they were being stopped by the police, they pulled over. The occupants of the SUV then approached their vehicles and stole money from them at gunpoint.

Police say the robbers were three or four men all wearing dark-coloured clothing and who did not identify themselves as police officers. The suspects' vehicle is possibly a GMC Tahoe or a similar model of truck.

Houghton said that undercover cop cars can be identified by the red and blue flashing lights positioned 360 degrees around the vehicle that "light up like a Christmas tree."

The blue flashing light in the suspects' vehicle looked more like a bike light flashing, he said.

Houghton advises that if you are being followed and are not sure whether you are being flagged by a police car, you can call 911 and find out in seconds.

To protect themselves, patrons can ask for free cheques instead of cash before leaving the casino, River Rock Casino spokesman Howard Blank told ctvbc.ca.