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DALLAS (AP) – A Dallas gang member must serve 21 years in prison for forcing his 16-year-old girlfriend into prostitution and advertising her availability online.

Trenton McLemore was sentenced Wednesday in federal court in Dallas. The 29-year-old McLemore in July pleaded guilty to sex trafficking of children.

Irving police arrested McLemore in September 2013 in an undercover operation targeting online soliciting and prostitution.

Prosecutors say McLemore provided his girlfriend, who was a runway, with a cell phone so she could communicate with commercial sex customers.

An Irving detective noticed a sex-related advertisement online and agreed to meet the girl at a motel room. Prosecutors say McLemore had been at the scene but left, leaving some personal items behind. He was later located and arrested.

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