A St. Albert man has been charged with two counts of personation of a peace officer after a pair of drivers were pulled over by an SUV flashing red and blue lights.

In one case, the driver was asked to submit to a "thumb scan" on a device carried by the suspect, police said in a news release Wednesday.

The man who has been charged is being investigated for other related offences, police said.

Westlock RCMP said they received a report on July 27 from a driver who had been involved in an alleged "traffic stop" conducted by a man who presented himself as a police officer.

The driver complained to police of being followed from Westlock by a light-coloured sport utility vehicle. The SUV activated red and blue lights as the two vehicles neared Fawcett, Alta., about 50 kilometres north of Westlock.

The driver pulled over to the side of the road. A man got out of the SUV and "presented himself as a police officer," RCMP said.

The driver was told that a traffic violation had prompted the stop. The driver was asked for a licence, vehicle registration and insurance.

"The documentation was returned to the complainant, who was then asked to have their thumb 'scanned' by a device presented by the man in question," police said.

Two days later, on July 29, Westlock RCMP received a complaint from the driver of a truck and trailer who had also been pulled over by a SUV similar to the one described in the first incident.

Again, the driver had been stopped near Fawcett by a man driving a light-coloured SUV.

In both cases, the complainants were unharmed.

During their investigation, police searched a St. Albert home and seized undisclosed evidence.

A 36-year-old St. Albert resident has been charged with two counts of personating a peace officer. He is scheduled to appear in provincial court in Westlock on Aug. 23.

Police are asking for help in locating a grey 2015 Chevrolet Suburban with black push-bars on the front bumper, tinted windows and black rims. The truck has Alberta licence plate BWL 2384.

Police said the truck is registered to the man who has been charged.