Staffers caught contractor Gregory Mahley, 51, of West Deptford peeking through an air conditioning vent at the Glen Landing Middle School, police in Gloucester Township said.
That's when they discovered that mirrors had been installed on the interior doors of the stalls in one of the girl’s bathrooms.
Police were called and Mahley was arrested on invasion of privacy and child endangerment charges.
Mahley -- who was sent to the Camden County Jail -- has worked for eight years with the Westville HVAC company Multi-Temp Mechanical, Inc., which police said cooperated fully with the investigation.
The Gloucester Township Board of Education contracted with the company for heating, ventilation and air conditioning services, they said.
Once they became aware of the incident, district officials "ordered a full inspection of all schools and facilities that Mahley may have had access to," according to a police report. " As of this time, no other suspicious activities have been uncovered."
Meanwhile, detectives were contacting businesses and governmental agencies for which Mahley may have worked.
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