A man has been charged with drug-related offences after Montreal police discovered and began to dismantle what they say is a drug laboratory producing fentanyl in Dorval

The force’s anti-gang unit received a tip that led them to a building on Lajoie Ave., in an industrial area close to the airport.

Police say the lab in that building was producing fentanyl, a powerful painkiller that is claiming lives across the country.

Officers have been at the scene since 9 a.m. Friday clearing out the stash. SQ officers are also at the scene helping with the operation. Police have declined to say how much of the suspected drug they found or where they believe it was destined.

Health Canada wasalso involved in the process, helping to identifying the various highly-toxis chemicals at the site as well as the drugs allegedly being produced there.

A 41-year-old man was arrested at the scene and has been charged with drug production and drug trafficking.

The building had a sign on it saying it was for rent. CTV Montreal called the number on the sign and spoke to a man who identified himself as the owner, but would not do an on-camera interview.

The man said he was frustrated because he rented the 15,000 square-foot unit to someone who then sublet part of it to the person allegedly operating the lab.

Subletting wasn’t allowed according to their agreement, he said.

Police at the scene were wearing hazmat suits and could only be inside the building for 15 minutes at a time before emerging to be decontaminated. None of the neighbouring units had to be evacuated.

Public health officials nationwide are warning street drug users about fentanyl, which is being mixed in with other drugs, sometimes without their knowledge. The opiod, often prescribed to cancer patients in severe pain, is being added to many street drugs to increase their potency. It is being sold in pill form as fake oxycontin and is also turning up in powdered heroin and being mixed into powdered cocaine and crystal meth.

Police also conducted a raid at a residence in Laval and confirmed they found an "unknown substance" at the house on Hubert-Aquin St.

The substance doesn't present a danger to the public, but will be sent for tests. Police set up tents and a stretcher as precautions while they searched the home.