Police say an opioid roughly 100 times more potent than fentanyl has been detected in drugs seized in an arrest on the West Shore last week.

Carfentanil was detected in a sample of heroin seized on Aug. 2 following a traffic stop in the 1000-block of Goldstream Avenue.

It’s the first time the dangerous drug has turned up on the South Island. It had previously been detected in drugs seized in Port Alberni and Nanaimo earlier this year.

“Carfentanil is about 100 times more potent than fentanyl,” said Staff-Sgt. Conor King of Victoria police. “There were over 900 overdose deaths in B.C. in 2016, and fentanyl played a part in many of those. While we were aware carfentanil may have already been here, this drug seizure confirms it.”

The traffic stop was the result of a joint investigation by West Shore RCMP and a Victoria police strike force and crime reduction unit.

Two men were arrested including Horst Francisco Shirmer, who was wanted on warrants for violating court-ordered conditions including a ban on possessing controlled substances.

A satchel of drugs was seized in the bust and officers found it contained cash, drug paraphernalia, more than a half-kilogram of cocaine mixed with fentanyl, meth mixed with fentanyl, marijuana, prohibited brass knuckles and a small packet containing the heroin and carfentanil mixture.

VicPD investigators detected the carfentanil, which is used to sedate large animals like elephants, using an ion scanner in a new negative pressure drug processing room.

Two men face charges in the incident. Shirmer remains in custody while the other unidentified suspect was released on a promise to appear in court.