Cody Wilson, the creator of 3D-printed gun designs who touched off a national debate in July over whether such files should be freely accessible to the public, was charged Wednesday with sexually assaulting a child last month in Texas.

A 16-year-old girl told Austin police that she had sex with Wilson, 30, at a hotel on Aug. 15 and was paid $500, according to authorities. The girl had created an online profile on SugarDaddyMeet.com, where she exchanged messages with a man who later identified himself as "Cody Wilson."

Wilson was in Taiwan, where he missed a scheduled flight back to the United States, Austin police said at a news conference. Before he left for Taiwan, he had been informed by a friend of the girl that she had spoken to police and that he was under investigation, said Austin Police Cmdr. Troy Officer.

Austin police were working with international authorities and the U.S. Marshals Service to locate Wilson. He frequently travels for business, but authorities don't know why he went to Taiwan, Officer said.

Wilson did not respond to attempts to contact him on Wednesday; a Houston lawyer representing Wilson in the 3D-printed gun matter did not immediately return a request for comment.

The alleged assault, first reported by the Austin American-Statesman, occurred about two weeks after a federal judge in Seattle put a temporary ban on Wilson's online publication of the gun-related files. On Aug. 22, the teen's counselor reported the assault to police.

Wilson used the profile name "Sanjuro" on the website; detectives matched his driver's license photo to the image in Sanjuro's online profile.

Wilson told the girl he was a "big deal," according to the affidavit. The girl did not know who he was but found news articles about him online. Wilson allegedly sent her photos of his penis, and she sent him a naked photo of herself.

The two met in the parking lot of an Austin coffee shop and then drove to a hotel in a car registered to Wilson's company, Defense Distributed. There, they had intercourse and oral sex, after which Wilson gave the girl five $100 bills, according to the arrest warrant. Wilson then dropped off the girl at a Whataburger restaurant.

Detectives matched the security footage, valet receipts, hotel receipt, and car registration from the day of the alleged assault to the girl's story and to Wilson's name.

Wilson, who has called himself a crypto-anarchist, became well-known for creating what was believed to be the first working 3D-printed gun in 2013. He was blocked, however, by President Barack Obama's State Department from distributing the files online under an arms export law. This spring, the federal government settled its case with Wilson, allowing him to publish the blueprints. He posted 10 files relating to 3D-printed guns in late July, one of which could be used to make a working gun.

A federal judge in Seattle blocked Wilson from posting online after attorneys general of 19 states and the District of Columbia sued Wilson, Defense Distributed, and the federal government. The ban is in place until the case is decided, but Wilson began selling and mailing the files instead.

Wilson also agreed in court to block Pennsylvania and New Jersey residents from accessing the site.

Wilson told the Inquirer and Daily News last month that he would fight any challenge to his dissemination of the files and "thought no matter what, there would be an outcome where I could post this stuff on the internet again."