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Press Release

Taiwanese Exchange Student Who Threatened to Shoot Up School Pleads Guilty to Federal Ammunition Charge

For Immediate Release
U.S. Attorney's Office, Eastern District of Pennsylvania

PHILADELPHIA – U.S. Attorney William M. McSwain announced that a Taiwanese exchange student pleaded guilty today to being an alien in possession of ammunition.  Sentencing is scheduled for December 11, 2018 before United States District Judge Nitza I. Quinones Alejandro. 

According to the Information, An-Tso Sun, 18, also known as “Edward Sun,” is a Taiwanese national who came to the United States in August 2017 on an F-1 visa to be a student at a high school in Upper Darby, Pennsylvania.  While attending school, he resided with a host-family in Upper Darby.  Beginning in October 2017, Sun visited a Philadelphia shooting range on multiple occasions, where he fired a variety of firearms, including semiautomatic rifles and shotguns.  Over the next few months, Sun purchased hundreds of rounds of ammunition from online vendors, and directed that they be shipped to his host-family address.  In January 2018, Sun purchased pistol components from multiple online vendors and assembled them to create a functioning homemade pistol. 

On March 26, 2018, after the school bell rang at the end of the day, Sun made the following statement to a fellow student:  “Hey, don’t come to school on May 1st . . . I’m going to come here armed and shoot up the school.  Just kidding.”  That student reported the incident to school officials, who then alerted law enforcement officials.  Upper Darby Police officers executed a search warrant at Sun’s residence and seized the following from Sun’s bedroom: 20 rounds of 9mm Blazer Brass ammunition; a ballistic suit, including a vest, jacket and pants; a crossbow; seven arrows; and various firearm accessories and shooting equipment.  Sun’s host-mother was later interviewed and explained that, prior to the search, she had removed a number of items from Sun’s bedroom, including bullets and firearm-related items, and given the items to an attorney.  Law enforcement took possession of those items, which included, among other things, a homemade semiautomatic pistol, two AK-style 30-round magazines with ammunition, two AR-15-style 30-round magazines with ammunition, and numerous additional boxes of ammunition, totaling over 1,600 rounds.

Sun was arrested by Upper Darby police and charged locally with making terroristic threats.  He pled guilty to that charge in early June and was sentenced to 4-23 months’ incarceration, with immediate parole, and credit for time served. He was released to the custody of U.S. Immigration and Customs Enforcement and charged federally by complaint on June 5, 2018.  He has been in federal custody since that time.

Under federal law, as a student present in the United States on an F-1 visa (a nonimmigrant visa) without a hunting license, Sun was not permitted to possess any ammunition or firearms.  Sun faces a maximum possible sentence of ten years’ imprisonment, a $250,000 fine, and three years’ supervised release.  As part of his guilty plea, Sun has agreed that upon completing his prison sentence, he is subject to immediate and permanent removal from the United States.

“Federal, state, and local law enforcement authorities will continue to work together to prevent tragedy and combat terrorism and threats of violence,” said U.S. Attorney McSwain. “As I have stated before, however, parents and guardians are the first line of defense in these kinds of situations involving children’s access to firearms. It should be obvious that no child should be stockpiling an arsenal – or have any access to firearms or other dangerous weapons – without their parents’ or guardians’ knowledge.  Every parent needs to be involved and actively aware of what is going on in their child’s life. It is their duty and obligation, not only to the child, but also to the community at large.”

“Sadly, threats of school violence have become all too common in this country,” said Special Agent in Charge Marlon V. Miller, Homeland Security Investigations Philadelphia Field Office. “Children in this country should feel safe in their school environment and free from the violence that terrorizes communities when these senseless acts occur.  Thanks to the quick action and diligent teamwork of federal, state, and local law enforcement in this particular case, a potentially devastating tragedy was averted.”

“In the case of An-Tso Sun, there is no question that this young man is a dangerous individual, who was armed with over 1,000 rounds of ammunition, ready to cause devastating harm to his classmates,” said Delaware County District Attorney Katayoun M. Copeland. “As the result of the swift response of his classmates, school officials, and the Upper Darby Police Department, no one was harmed, and Mr. Sun is now rightfully facing the severe consequences of his actions. I would like to commend Homeland Security Investigations and the Upper Darby Police Department for leading this investigation and thank United States Attorney William M. McSwain and the United States Attorney’s Office in the Eastern District of Pennsylvania for pursuing federal charges in this case and ensuring the safety of our residents.”

This case was investigated by the Department of Homeland Security, Homeland Security Investigations, with the assistance of the Upper Darby Police Department and the Delaware County District Attorney’s Office, and is being prosecuted by Assistant United States Attorney Sarah M. Wolfe.

Updated August 28, 2018