An officer with the Toronto Police Service's drug squad died of a fentanyl overdose earlier this year, prompting police to conduct an investigation.

In a statement released Thursday, Acting Chief Jim Ramer said Const. Michael Thompson was found at his home in medical distress on April 10, 2017.

He was rushed to hospital, where he died three days later.

Police confirm it was later determined that Thompson died from a fentanyl overdose.

According to police, the amount of fentanyl found in his system was “too large to have been caused by mere contact with that drug.”

Ramer called Thompson a “good police officer who was respected by his colleagues.”

An investigation has been launched into the circumstances surrounding the officer’s death but police say “many questions remain unanswered.”

Police say the officer had regular access to street-level drugs and added that some of the cases he was involved in were due to go before the court starting Monday.

“By working with the Crown, the Service has learned that because of his death, and the circumstances under which it happened, changes will be made to how these cases proceed, or not, through the justice system,” Ramer’s statement read.

“Our condolences remain with his colleagues, including the dedicated and professional members of the Drug Squad, Michael’s family and friends who have all been devastated by his passing.”