Cody Wilson, founder of the 3D-printed gun firm Defense Distributed, has been accused of sexual assault of a minor last month, a second-degree felony. In a press conference today, the Austin Police Department said the self-styled "radical libertarian" and gun-rights activist was last seen in Taipei, Taiwan and that he missed a flight back to the United States.

APD Commander Troy Officer said at a press conference this afternoon that he wasn't sure when Wilson left the country for Taiwan – which doesn't have an extradition agreement with the United States – but that the 16-year-old minor sought counseling after the encounter on Aug. 15. The counselor then alerted the authorities.

"I'm not even trying to guess Mr. Wilson's motive," Officer said, "but we do know that based on the victim and investigation, he had sexual contact with a 16-year-old girl, which in the state of Texas is illegal."

According to an arrest warrant, Wilson connected with the unidentified minor on the site SugarDaddyMeet.com, suggesting to her that he was a "big deal" and later identifying himself as Cody Wilson. Wilson is alleged to have sent a naked photo of himself and the minor also sent him a naked photo, as well, before taking their conversation off the site and arranging to meetup over text.

Officer said investigators believe the minor signed herself up for the site, which does not allow minors to register an account, but said that the site is not currently a part of the department's investigation.

"At this point, we're focusing on the victim," Officer said.

On Aug. 15, they met for a few hours at a coffee shop on South Congress Avenue before heading to the Archer Hotel near the Domain. Police say valet receipts, security camera footage and the hotel's records confirm Wilson was at the hotel with the minor, who stated that she and Wilson had sex before he handed her five $100 bills. Wilson then, the warrant states, dropped her off at a Whataburger in South Austin.

The warrant charges Wilson with sexual assault and places his bond at $150,000. Wilson faces as many as 20 years in prison and a $10,000 fine.

Recently, Wilson and his firm Defense Distributed were locked in a protracted legal battle to make plans to fabricate 3D-printed guns readily available online. The Department of Justice allowed the move earlier this summer. Attorneys general in 19 states and the District of Columbia filed a successful suit to block the move. The firm now supposedly disseminates the plans through flashdrives mailed directly to customers.

Read Wilson's arrest warrant below.

This story has been updated.