In another case of online ads being used for sex trafficking, a Duluth man and woman are accused of selling teenage girls for sex in several states through Backpage.com.

In an indictment unsealed Monday in federal court, Markeace Arque Canty, 32, has been charged with sex trafficking of a child and receiving child pornography.

St. Louis County Attorney Mark Rubin said Canty conspired with Tabbatha L. Olson, 22, of Duluth, to engage several girls from Duluth in sex trafficking and used online ads to attract customers. He said Olson has been charged by the state with aiding and abetting sex trafficking.

From July 2012 until January, according to the indictment, Canty bought "escort" ads on Backpage.com and offered a girl for erotic encounters. The ads sometimes included photos of a girl who was no older than 17.

The indictment against Canty said he bought a Backpage escort ad in northwestern Indiana in September. That caught the eye of authorities, who set up a sting at a motel in Valparaiso, where the girl offered sex for $200 an hour and was arrested.

Canty is charged with selling the girl for sex in Minnesota and Indiana.

Canty's criminal history in Minnesota includes two felony convictions for drug possession and another for witness tampering. Olson is in the St. Louis County jail.

Last year, police linked Backpage to underage sex trafficking, prompting the Minneapolis and St. Paul city councils and the Hennepin and Ramsey County attorneys to ask Backpage to halt the ads.

Paul Walsh • 612-673-4482