Officers responded about 8:25 a.m. Monday to the AGC satelitte warehouse, 31 Hunter Place, on an alleged bomb threat.
Employees of that location were evacuated and reported to the main factory, 1465 W. Sandusky Ave.
The facilities coordinator reported a handwritten message was located on a bathroom stall.
The Allen County Regional Bomb Squad responded about 10:30 a.m. and conducted a sweep of the building with canine units. No suspicious devices were found.
Video surveillance will be reviewed to identify potential suspects.