A 23-year-old Ukrainian national who posed as a teen to attend a Pennsylvania high school was charged Friday with sexual assault over a relationship with a student.

Artur Samarin, already jailed on identity theft and other charges, was arrested on charges of statutory sexual assault and corruption of minors, Harrisburg police said in a statement.

The new charges stem from a sexual relationship in 2014, when the student was 15 and Samarin was 22.

Samarin, using the alias Asher Potts, enrolled in Harrisburg High School as a freshman in 2012 and was a member of the National Honor Society and the school's ROTC and Naval Sea Cadet programs. He was to graduate in June.

Authorities say he came to the U.S. on a three-month work visa then got a tourist visa that expired in March 2013. He enrolled as a freshman six months later.

Police were alerted to Samarin by a tipster in December who alleged Samarin was an adult living illegally in the U.S. and was having sexual relationships with female students.

Two people helped enroll a Ukrainian man in a Pennsylvania high school with a fake identity, according to a criminal complaint obtained by Pennlive.com.

The complaint alleges Stephanye McClure-Potts and Michael Potts helped enroll Samarin with documents that listed his birthday as Sept. 3, 1997. His actual birthday is Sept. 3, 1992.

The complaint says McClure-Potts also helped Samarin get a Pennsylvania driver's license under the name Asher Potts in 2014.

McClure-Potts and Michael Potts haven't been charged. A man who answered the phone at a listing for McClure-Potts hung up on an Associated Press reporter seeking comment.

Samarin graduated from high school in Ukraine, police said Friday, and attended two years of college there.

He was arrested Tuesday and faces charges including theft, identity theft and records tampering. Online court documents don't list attorney information for him.

The investigation is ongoing and additional arrests are expected, police said.