Snapchat app. (Lionel Bonaventure/AFP/Getty Images)

Federal authorities in Tennessee arrested and charged a man with intent to extort money from a woman on the social media app Snapchat, after he led her to believe he was a University of Tennessee football star — and threatened to share nude photos of her on the Internet unless she took more pictures and sent them to him.

Brandon Douglas Shanahan, 22, of Sweetwater, Tenn., pleaded not guilty Wednesday in the extortion scheme and has been released on bond, the Justice Department said.

Shanahan communicated on Snapchat with the woman and led her to believe that she was chatting with Cameron Sutton, a University of Tennessee defensive back, according to a criminal complaint filed this week in U.S. District Court in Tennessee.

In April, the female victim, identified in court documents as C.C., told the FBI she had been communicating for weeks with a person whose screen name was “Camsutton2323,” believing it was the football player with the same name and jersey number.

Sutton has twice been named Sporting News First Team All-American as a punt returner and is considered a top NFL prospect, according to ESPN.

In the beginning, the victim told authorities, “Camsutton2323” was sending her messages such as “you’re a goddess” and “you’re beautiful,” according to the documents.

She told investigators that the conversation had been fairly one-sided, but that she decided to “give him a chance” — giving him her phone number and sharing more personal details, such as where she was from and the name of her roommate, according to the documents.

The woman told authorities that “Camsutton2323” sent her a photo on April 9 showing an African American man’s torso with a large tattoo wrapped around the rib cage.

That Saturday night, she told them, she went out to a bar and got “very drunk” — snapping pictures of herself and of the bar and then sharing them on her “Snapchat story,” a live feed where users post photos and videos for their followers to see.

The woman told the FBI that later that night, “all I remember is taking off my clothes and getting into bed,” according to the court documents.

Inmate Brandon Douglas Shanahan. (Blount County Sheriff’s Office)

The next morning, C.C. told authorities, “Camsutton2323” told her she had taken nude photos of herself while she was drunk and sent them to him, according to court documents.

Although the woman said she did not believe she had done so, she had no way of knowing for certain: After a photo is viewed on Snapchat, it is erased within a few seconds.

The woman told authorities he said he would post the photos on social media unless she took more nude photos and sent them to him.

She said she then started getting calls from a blocked number; the man on the other end of the line, she said, ordered her to use graphic language to say that she wanted to have sex with him.

During one conversation, she told authorities, he mentioned that he had been shot in the past — later telling her, “I’m going to put you what I went through,” according to the court documents.

Authorities said she “believed the caller was insinuating that he would shoot her based on the earlier comment that he had been shot,” according to the documents.

At one point, she said, she told him: “I’m terrified, please stop.”

“Please, I’m begging you,” she later reiterated, records show.

Authorities said that “under duress” the woman finally relented, sending photos of herself in a bikini and in her underwear.

“I have never been more scared in my life,” she told investigators.

FBI agents traced the caller’s phone number to Shanahan.

Federal investigators believe Shanahan may have had “numerous” other female victims, according to the Justice Department.

Shanahan was arrested and charged Tuesday for attempting to extort the woman by threatening to ruin her reputation, federal authorities said. Shanahan pleaded not guilty and was released on bond. It’s unclear who is representing him.

If convicted, he faces a maximum of two years in prison.

The investigation also revealed that “Sutton himself was a victim of criminal impersonation,” according to a Justice Department statement. “Sutton had not conversed with the victim via Snapchat or any other method of communication and had no knowledge of Shanahan’s impersonation of him.

Ryan Robinson, the University of Tennessee’s senior associate athletics director for communications, said in a statement that the school’s administration was “aware of the investigation and very appreciative of the work law enforcement did in this matter.”

Sutton, a junior, was named co-captain of the Tennessee football team in April.

Three months earlier, he announced on Twitter that he would return for his final season with the Vols instead of leaving for the NFL draft.