Pinery Provincial Park officials have decided to close the park after individuals told the Ministry of Natural Resources and Forestry of a plan to occupy it.
In a Tweet, park officials said they were working with the OPP to ensure safety of campers and staff.
"These situations are complex. We are working with the OPP to dialogue with the occupants as we need to fully understand their assertions and interests. We want to conduct ourselves in a way that best ensures the safety of our campers and staff and safeguards the park."
OPP Sgt. Dave Rektor said provincial police have been involved in talks but there is nothing further to add at this time. "The issue relates to land claims and is before the courts."
The park will be closed to the public for camping and day use until further notice, authorities say.