Toronto police said they have dismantled the Monstarz gang, which operated in the city's northwest and was allegedly involved in eight homicides with a rival gang.
The investigation into the gang began in September 2014, which led police to various other organizations, including one that involved the Hamilton police officer, Insp. Bryan Bott said at a news conference that displayed the guns and drugs they seized.
It was a massive investigation, dubbed Project Pharaoh, that involved forces across much of southwestern Ontario as well as the Canada Border Services Agency.
Police made 60 arrests and 45 people are currently facing 379 gun, drug and organized crime-related charges.
Hamilton police officer Craig Ruthowsky, 41, faces four charges, including breach of trust, conspiracy to traffic cocaine and two counts relating to organized crime.
Ruthowsky has been suspended with pay since June 2012 for allegations from a separate investigation, according to Hamilton police Supt. Dan Kinsella.
"Since that time, that member has had no contact with the public as a police officer," Kinsella said. "Those allegations are currently before the police tribunal."
Bott said the alleged involvement of a Hamilton police officer had an impact on the investigation.
"We didn't involve Hamilton in a lot of our efforts because of that," he said.
Insp. Jim Ramer described the Monstarz gang that led them to the officer as a mid-level criminal organization that has been involved in 44 violent incidents since May 2011.
He described one incident that took place on May 30, 2014.
A Monstarz gunman allegedly opened fire in an apartment complex and shot two men and one woman, Ramer said. A friend drove one of the shooting victims to Etobicoke General Hospital.
When the friend left the hospital, he was shot, Ramer said. The gunman sprayed bullets into the hospital.
"Patients and hospital staff were then sent diving for cover," he said. "It was through sheer luck that no innocent victims was wounded or killed."
Bott called the actions of the Monstarz gang "despicable."
He said much of the violence was due to a feud with a rival gang that forced the Monstarz to expand its operations outside of Toronto.
"I believe we've taken out a significant portion of this gang," Bott said.
More than 700 officers were involved in the operation. Police said they seized 33 kilograms of cocaine, nearly $200,000 in cash and 15 vehicles.
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Note to readers: This is a corrected story. A previous had a misspelling of Ruthowsky's name.