Man in Custody for Posing as High School Student Accused of Having Sexual Relationship With Teen "Asher is 18 years of age and Artur is 23," he told WHTM. "It was not my idea."

 -- A 23-year-old man in custody accused of posing as a teenager and attending a Pennsylvania high school is now facing more charges for allegedly having a sexual relationship with a 15-year-old while he was 22.

Artur Samarin, who went by the name "Asher Potts," was charged Friday with statutory sexual assault and corruption of minors for his alleged sexual relationship with a 15-year-old student in 2014, the Harrisburg Police said. Police say Samarin was 22 at the time.

Samarin had not yet been arraigned on these charges as of Friday, the police said.

Samarin was first identified by police on Dec. 11 when the Harrisburg Police received a complaint alleging that a student attending John Harris High School named “Asher Potts” was Samarin, an adult in the U.S. illegally, who was having sexual relationships with female students, according to police.

An investigation "determined that Samarin arrived in the U.S. on a 3 month J1 Exchange Visitor Visa from June to September," said the Harrisburg police. "He was working for a local company during that time. After the Visa expired, he applied and was granted B2 Tourist Visa. The B2 Visa expired on 3/1/2013."

Police say Samarin graduated high school and attended two years of college in the Ukraine, but then in the fall of 2012, he enrolled as a freshman at John Harris High School with "falsified documents," including a social security card "that was ultimately approved after multiple attempts at several Social Security Administration offices."

Samarin attended John Harris High School "until recently," police said, adding that he also attended Harrisburg University.

Steven Infanti, Associate Vice President of Communications at Harrisburg University of Science and Technology, told ABC News today that Samarin was enrolled in a dual enrollment program through the high school, which lets high school students attend classes at the university. He was enrolled in Spring 2015, Fall 2015 and was attending classes this semester, although he's not anymore, Infanti said. Infanti said he could not provide further comment due to the ongoing investigation.

John Harris High School and the Harrisburg School District could not be immediately reached for comment.

On Tuesday, Samarin was arrested for identity theft, theft by unlawful taking and tampering with public records and placed at the Dauphin County Prison in Harrisburg on $20,000 bail, police said.

In response to those three charges, Samarin told ABC affiliate WHTM, "I am guilty."

"I did abuse the system. Yes I did. I did use this identity," he said in a phone interview with WHTM from the Dauphin County Prison. "I’m here in this prison because I’ve done a crime. I’m a criminal, unfortunately, but it is true."

The statutory sexual assault and corruption of minors charges were added Friday.

WHTM said that it "was not aware of the additional charges when Samarin called from prison so he was not given an opportunity to respond."

Samarin told WHTM he came to the U.S. from Ukraine in 2012 for a better life. He claimed when his visa expired, Michael and Stephayne Potts offered to adopt him.

“Stephayne came up with the idea that 'we are going to adopt you,'" he told WHTM. "'We are going to bump five years of age.' ... I said, ‘OK, looks like I have no choice.'"

"Asher is 18 years of age and Artur is 23," he said. "It was not my idea."

Samarin told WHTM the Potts' helped him get a birth certificate with the name "Asher Potts" and a birth date in 1997, as well as a social security card.

Numbers listed for Michael and Stephayne Potts could not be immediately reached by ABC News today.

Samarin, who told WHTM he was a straight “A” student at John Harris High School, said he does't regret enrolling.

"I have spent all of my free time on education. It’s all about education. I tried to do better for the society," he said.

"I love the United States," he said. "It’s a land of opportunity for all of us immigrants and this land provided me with opportunities."

Police say additional arrests are expected. The U.S. Department of State, FBI, the Ukrainian Embassy and Immigration and customs are involved in the ongoing investigation.