An Tso Sun, Darby
A foreign exchange student from Taiwan allegedly threatened to shoot up Bonner and Prendergast Catholic High in Drexel Hill. Photo: Upper Darby Police Department

A foreign exchange student from Taiwan was arrested Tuesday evening after allegedly threatening to carry out a mass shooting at a Drexel Hill high school, police said.

 

An Tso Sun, 18, was arrested after police got word that he allegedly said he was going to go on a May 1 shooting spree at Bonner and Prendergast Catholic High, where he is a student. Sun now faces charges of making terroristic threats.

 

Police Superintendent Michael Chitwood said Upper Darby investigators were tipped off by another student who said Sun warned him not to come to school on May 1 and asked him how to purchase a gun.

 

“He was planning something terrible,” Chitwood said at a news conference on Wednesday. “We have zero tolerance for any threats at any of the schools. Anybody that makes any threats to shoot, bomb or hurt anybody in the schools is going to get locked up. Period.”

 

Though Sun told the tipster he was “kidding” about the threat, police said they found an iPad allegedly used by Sun to research firearms like AK-47s and AR-15s, and he allegedly showed the tipster a video of a flamethrower and a mask. Back in February, Chitwood said, Sun showed off a high caliber bullet while at school.

Upper Darby detectives with a search warrant searched Sun’s host family’s home on Le Carra Drive in Landsdowne on Tuesday and allegedly found a high-powered crossbow with scope and light, seven arrows, a loading dock for AR-15s and AK47s, a military-style ballistic vest, a military-style backpack for holding clips and a strangulation device called a garrote. Police said they also found a ski mask and ear protectors. Chitwood unveiled the seized items at Wednesday’s news conference.

Sun is being held on $100,000 bail, and federal authorities have been made aware of the investigation. Chitwood said Sun was undergoing a psychological evaluation at a Delaware County prison. Sun is in the United States on a student visa that was issued in July 2017.