Jul 3, 2014 1 min read

PITTSBURGH (AP) — Pittsburgh police have been investigating the theft of chemicals from a laboratory at the Community College of Allegheny County.

Police and school officials aren’t saying what kind of chemicals were stolen, only that is appears someone entered the lab and improperly mixed some chemicals before also taking some sometime between Monday night and Tuesday morning.

That’s when an employee of the school’s North Side campus noticed a door to the lab was propped open.

When school officials investigated, an inventory determined some chemicals were missing.

City public safety spokeswoman Sonya Toler says police continued to work with school officials to determine which chemicals are missing and who might have taken them.

The school has tightened security rules and has been requiring employees and students to show school identification upon request.