SABATTUS — Athletic fields at Oak Hill Middle School were closed Thursday after some students developed rashes, Superintendent James Hodgkin said.

Over the weekend, the fields were treated with a fertilizer the school and Sabattus Recreation Department hadn’t used before, Hodgkin said. By Wednesday, “less than five students” got skin rashes after being on the fields.

“We closed the fields as a precautionary measure,” Hodgkin said. “There were a number of kids who developed rashes. It could be a coincidence. We didn’t let them have practice.”

The fertilizer came from the Maine Department of Agriculture. Hodgkin said he has no idea if the rashes and fertilizer are connected.

On Thursday, the fields were watered and inspected.

“We couldn’t see anything,” Hodgkin said. “Our intent is to open them tomorrow.”