AUGUSTA — A Portland man was arrested on drug charges by city police Thursday after a traffic stop allegedly led to the discovery of heroin.

The man, Preston Cooper, 52, was charged with aggravated trafficking of scheduled drugs, unlawful possession of scheduled drugs, sale and use of drug paraphernalia, and operating while license suspended or revoked.

In a news release Friday, Detective Sgt. Jason Cote, of the Augusta Police Department, said police received a tip at 1:30 a.m. Thursday about a suspicious vehicle that was “traveling to Augusta and possibly transporting a large amount of drugs.”

Patrol officers found the vehicle about 2 a.m. on Winter Street and pulled it over for a traffic stop, as the driver, Cooper, had a suspended license. Officers searched him and the vehicle and found 30 grams of heroin with an estimated street value of $6,000, according to the release.

Cooper was unable to post $60,000 cash bail and was taken to the Kennebec County jail in Augusta, police said.