Military Vest, Other Items in Student’s Home Were “Halloween Outfit,” Says Lawyer

An attorney for An Tso Sun, the 18-year-old charged with terroristic threats against an Upper Darby high school, said items found in Sun's residence were part of a "Black Ops" outfit.

upper darby

Photo via the Upper Darby Police Department

This is a developing story and may be updated at any time.

Police in Delaware County have arrested an 18-year-old exchange student who they say threatened to conduct a shooting at a Catholic high school in Upper Darby.

According to court documents, An Tso Sun was charged with threatening to terrorize Bonner Prendergast Catholic High School, located on North Lansdowne Avenue in Drexel Hill. Sun was allegedly found to have a military vest and ammunition at his residence.

Sun was arrested on Monday and charged with terroristic threats. He is currently being held in Delaware County Prison on $100,000 bail.

Police say Sun is from Taiwan. Speaking at a press conference on Wednesday morning, Upper Darby police superintendent Mike Chitwood said another student claimed that Sun told him not to come to school on May 1st because Sun said he was “going to shoot up the school” that day. Chitwood said Sun later claimed he was joking.

After the student reported the alleged threat to a teacher, police said they found a school-owned iPad that Sun had used to “look into” guns like AK-47s and AR-15s. Around 9 p.m. on Tuesday night, police executed a search warrant at Sun’s host family’s home. Chitwood said they found:

  • A military-style ballistic vest
  • A backpack with pouches to hold ammo clips
  • A high-powered crossbow and seven arrows
  • A loading dock for AK-47s and AR-15s
  • 20 rounds of 9mm ammunition
  • A military ski mask
  • Ear protectors for firing
  • A strangling device

“That’s a lot of stuff,” Chitwood said. “I have a lot of concern over it. When you add it all together, we believe that he was planning something horrible.”

Sun’s lawyer, Enrique Latoison, said some of the items found were part of a Halloween costume that Sun wore to school.

“Those items have a harmless context,” Latoison said. “It was a ‘Black Ops’ outfit that he actually wore to school.” 

When asked about specific items, Latoison said he had yet to see the full list of items that were allegedly found at Sun’s residence.

“I don’t know anything about the strangling device,” Latoison said. “I don’t think that people are irrational for having a heightened sense of fear when you put everything together. But what I’m saying is that he had no intention to harm anyone, to go and shoot anyone. He had no intentions of committing any kind of mass shooting.”

In response to Latoison’s claim, Chitwood said, “That’s a good one.”

“It’s a tactical army ballistic vest,” Chitwood said. “It probably weighs 80 to 90 pounds. There’s a strangling device. There are 20 rounds of 9mm ammunition. When you put it all together, then you have to raise questions. By themselves, [the items are] not illegal. But when you add it all up, it shows a pattern of potential horrific, horrible acts that could be committed. “

Chitwood stressed that the investigation is active and ongoing.

Sun is reportedly expected to undergo a psychological evaluation. His host family is reportedly American.