BALDWIN (KDKA) — Students at Paynter Elementary School in the Baldwin-Whitehall School District only spent a couple of hours in the classroom Monday before one phone call sparked an intensive search and evacuation.

Baldwin Borough Police Chief Michael Scott talked to KDKA’s Kym Gable about the investigation at the elementary school.

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“We started an investigation. We had bomb dogs come in from several communities to check out our school,” he said.

Chief Scott confirmed that federal authorities are now investigating.

“Seeing the similarities between several of them [local bomb threats], and coordinating at our level, we contacted the FBI for assistance,” said Chief Scott.

Baldwin-Whitehall Superintendent Dr. Randal Lutz added,” The amount of resources dedicated to this today – not only our own staff, but police, EMS, bus drivers. We had parents getting phone calls. Hundreds and hundreds of parents felt the need to pick up their children.”

Students at Paynter were initially taken to the nearby municipal complex, and then bused to Harrison Middle School.

It was the same circumstances at Richland Elementary School in the Pine-Richland School District. The school office also received a phoned-in threat.

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There were several scares at local schools Monday.

Officials have confirmed two had messages that were recorded and automated – those being Pine-Richland and Paynter elementary schools. Across the country, schools in Colorado, Delaware, Minnesota, New Hampshire and Wisconsin were also evacuated.

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In a crime called “swatting,” officials say hoaxers have used online proxy servers and other high-tech tools to anonymously threaten schools, possibly through robo-calls.

The most recent cases are now part of a nationwide investigation.

“Seeing the similarities between several of them, and coordinating our level, we contacted the FBI for assistance,” said Chief Scott.

“It does disrupt everybody, for which may be nothing but a prank, so it’s very frustrating,” Dr. Lutz added.

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The last time this happened on such a broad scale was back in February, and investigators say those robo-calls were likely coming from a group in Russia.