Seven Toronto police officers have been arrested in connection to a major investigation by York Regional Police (YRP), a source confirms to CityNews.

Four of the officers have been suspended without pay.

The source tells CityNews the investigation originated in Toronto by the Toronto Police Service, but under new rules, they gave up the investigation and sourced it out to an unbiased force, which was YRP.

YRP officers are set to announce the results of a major investigation into organized crime and corruption on Thursday morning.

A statement sent out by the York Regional Police Service (YRP) Wednesday afternoon described the investigation, dubbed “Project South,” as one that was “lengthy.”

YRP Chief Jim MacSween and Deputy Chief Ryan Hogan are set to speak at the service’s headquarters in Aurora on Thursday alongside Toronto Police Chief Myron Demkiw. The news conference is scheduled for 10 a.m. and it will be live-streamed on CityNews 24/7.

The Toronto Police Association confirmed in a statement Wednesday night that several of their members have been arrested.

The association said they had no further comment regarding the investigation or the police officers involved.

This is a developing story that will be updated.