A 24-year-old convicted sex offender is accused of having sex with a 14-year-old at the Occupy Dallas campground near City Hall, police said.
Dallas police said Richard Wayne Armstrong was arrested Sunday on suspicion of having sex with a 14-year-old runaway.
Police said the girl told Armstrong and others at the Occupy Dallas camp that she was 19.
"You know, different people can see it different ways, but once you talk to her, I think it's a little bit obvious that she was younger than she said," Deputy Chief Sherryl Scott said.
Occupy Dallas demonstrator Sarah Peace said had spent time with the teenager and was shocked to learn she was 14.
"She was here for quite some time, and she and that man, well, they were together," Peace said. "They hung out all the time. Not only did she hang out with him, but she hung out with three or four of the other guys -- they all hung out together."
Officers located the girl after receiving information Oct. 23 that a girl at the camp matched the description of a runaway from Garland.
The girl told detectives she had sex with a 24-year-old man in a tent at the Occupy Dallas encampment.
Police located and questioned Armstrong and discovered he had failed to register as a sex offender after he recently got out of prison in Big Sandy.
Armstrong was convicted of sexually assaulting a 14-year-old girl in Coppell in 2009.
People at Occupy Dallas' camp said they do not question protesters about their backgrounds.
"We have opened a call to say, 'This is the movement of all people,' so it's hard to say anyone is not part of this movement," demonstrator Andrew Louis Davis said.
Dallas police said the Occupy Dallas campsite is safe but could be seen encouraging parents to take their children someplace else Tuesday.
"We are concerned about the general welfare of the children. Make no mistake about it -- that's all this visit is about," an officer told a demonstrator.
Members of Occupy Dallas said teenage runaways and sex offenders are not welcome at the camp.
"This situation is not one that we would have wanted to have happen, but it is something that we needed to learn," Peace said.
"We're all actually here for beautiful ideas and dreams that we have," she said.
Occupy Dallas has a 60-day permit that allows the camp to remain behind City Hall until mid-December.
Armstrong is charged with failure to register as a sex offender and sexual assault of a child, both felonies. He was taken to Lew Sterrett Justice Center and was still in custody Tuesday night.
His bond was set at $200,000.
NBC 5's Ken Kalthoff and Ellen Goldberg contributed to this report.