The Royal Canadian Mounted Police (RCMP) announced Tuesday that it has commenced a criminal investigation into the Ontario government’s plan to develop portions of the “Greenbelt,” a large area of protected land in the province’s south.

While the RCMP, Canada’s federal police force, did not disclose the specifics of the the investigation, it said that a Sensitive and Internal Investigations (SII) unit is undertaking the probe. SII units investigate corruption and political offenses.

Beyond these revelations, the RCMP declined to provide further information. The force said in its statement, “While we recognize that this investigation is of significant interest to Canadians, the RCMP has a duty to protect the integrity of the investigations that it carries out, in order to ensure that the process leads to a fair and proper outcome.”

The investigation stems from a plan by Ontario Premier Doug Ford and his government to open portions of the Greenbelt, two million acres of protected land near the most densely populated part of the province, to private development. Two weeks after Ontario’s Auditor General released a report finding that certain developers were given “preferential treatment” as part of the plan, the RCMP confirmed that it was mulling an investigation over the affair following a referral by the Ontario Provincial Police.

Last month, Ontario Municipal Affairs and Housing Minister Steve Clark resigned after Ontario Integrity Commissioner J. David Wake found that Clark breached the province’s Members’ Integrity Act by failing to properly oversee the development selection process. The report stated that Clark’s chief of staff presided over a flawed land re-designation process by allowing developers who proactively approached him to have their land removed from the Greenbelt instead of making a public call for submissions.

The Integrity Commissioner and the Auditor General opened separate investigations into the matter in January after accusations emerged that the Ontario government told developers about the plan before it was made public.

Ford reversed his decision to open the lands up for development on September 21, citing a previous promise to protect the Greenbelt.