(CNN) YouTube singer Austin Jones has been sentenced to 10 years in prison for asking underage girls to send him sexually explicit videos of themselves to prove that they're fans.

Jones, 26, crooned a capella covers of popular songs and performed on tour nationwide. Most of the fans of the suburban Chicago singer were teenage girls.

In 2017, he was arrested on two counts of production of child pornography. Jones admitted to enticing six underage girls to make pornographic videos of themselves and send them to him, according to a plea agreement. The girls were as young as 14.

He pleaded guilty in February, and on Friday, US. District Judge John Z. Lee sentenced him to 10 years in federal prison.

"Production and receipt of child pornography are extraordinarily serious offenses that threaten the safety of our children and communities," Assistant U.S. Attorney Katherine Neff Welsh said in the government's sentencing memorandum. "Jones' actions took something from his victims and their families that they will never be able to get back."

To get the videos, Jones told some of the girls "to 'prove' they were his biggest fans," that they "were part of a modeling opportunity, and that he could assist them in gaining followers on Instagram," the Department of Justice said.

Jones admitted using Facebook to persuade minor girls to send him pornographic videos and pictures approximately 30 other times.

He messaged girls as young as 14

Even before his arrest, Jones had come under fire for his interactions with young fans. In June 2015, he posted a 16-minute YouTube video in which he looked directly into the camera and admitted that he used to ask fans to send him twerking videos.

"Nothing ever went further than twerking videos," he said. "There were never any nudes, never any physical contact."

Jones was first arrested in June 2017 at O'Hare International Airport and questioned in a recorded interview, the complaint states. He waived his Miranda rights and admitted to using Facebook to have sexually explicit chats with underage girls, receive explicit videos from them and view those videos for sexual pleasure.

He instructed them on what to say

A federal criminal complaint cites two instances of Jones messaging teenage girls to send him explicit videos of themselves dancing.

In one example, Jones messaged with a girl who told him she was 14 years old. Jones allegedly asked her to send videos of herself dancing in a sexual manner and referred to it as a "try out" and an "opportunity."

According to the complaint, Jones instructed the girls on how to shake or "clap" their buttocks and expose themselves in videos for him.

"At the beginning, get super close and say these lines: hey Austin, it's (name) and this butt is (age) years old and then make it clap for 30 seconds. Got it?" Jones wrote on Facebook to the girl, the complaint states.

She ultimately sent him about 15 videos of her dancing, including 10 videos in which she exposed herself, the complaint states.