WASHINGTON — A foreign exchange student is in custody after the sheriff’s department says the man sexually assaulted a 17-year-old in Stafford County.

On Saturday, Stafford County Sheriff’s Office Deputy Thomas Grasso responded to a Stafford County residence for a possible domestic disturbance. While Grasso was investigating, he learned that 20-year-old Hamad Mastour Alsuwat — a foreign exchange student living in the residence — had sexually assaulted a 17-year-old girl who lived there.

Alsuwat was not at the residence when police responded.

Stafford County officials contacted the U.S. Department of Homeland Security in the chance that Alsuwat was a flight risk.

U.S. Customs and Border Protection arrested Alsuwat on Sunday as he was preparing to board a flight out of Washington Dulles International Airport bound for Saudi Arabia.

Alsuwat is charged with object sexual penetration.

Officials have not said where Alsuwat attended school as a foreign exchange student.

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