CHICAGO (CBS) — An Iowa couple has pleaded guilty to luring two Chicago teens to Waterloo to work as prostitutes.

Assistant U.S. Attorney Tim Duax says Lawrence Edward Campbell Jr. and his wife, Sade Desire Campbell, used social media to convince two 16-year-old Chicago girls to go to Waterloo to be taken care of.

Prosecutors say the Campbell’s sent the teens bus tickets, brought them to the couple’s home, then took them to two hotels and a home to meet men for sex.

Duax says troubled teens are often targeted in the same way on social media, adding, “The predictors tend to look for kids who are having difficulties at home.”

Duax says the Campbell’s kept all of the money men paid for the girls, and brought them to a shopping center to shoplift items they could sell to make additional money. Waterloo police say they caught the girls shoplifting at a Target, which led investigators to the Campbell’s.