Reports of a masked intruder forced a temporary evacuation of 550 students at the Edward H. Bryan School shortly after noon today.
Local officials suspect a Verizon worker, confused for a suspected intruder, caused the scare.
The incident is still under investigation, Police Lt. Michael Marino said.
"At this time we are not quite sure, [but] you have to act first and make sure everyone was safe," the lieutenant said.
Marino said that several shaken students first reported seeing a man dressed in dark clothes with a mask enter the building.
District Superintendent Charles Khoury confirmed that there was a workman who signed into the building at the time. But Principal Phyllis Weinberger decided to call the police after hearing the complaints, Khoury said.
The police raced to the scene and evacuated the elementary school within minutes.
With backup assistance from Demarest, police followed emergency protocol and secured the perimeter of the school. They then conducted a thorough sweep of each classroom, Marino said.
There were no intruders found at the scene.
After 45 minutes, the police then allowed students and staff to return to the building and proceed with the third lunch period of the school day.
The superintendent quickly posted a letter on the school Web site and issued an automated phone recording to concerned parents.
"I commended both the staff and police," said Khoury. "Our emergency plan kicked in and everyone did what they had to do."
