A federal jury in Texas has convicted a San Antonio man of trying to sell his girlfriend's 5-year-old daughter to child pornographers in exchange for a used car and an apartment.

Forty-year-old Sean Michael Block could be sentenced to up to 30 years in prison following Friday's verdict.

The San Antonio Express-News reports that girlfriend Jennifer Richards testified Block threatened her into complying with his plan to sell her daughter. The defense contended Block's was engaging in a sting operation aimed at the 25-year-old waitress.

The girlfriend previously pleaded guilty to similar charges in return for a 20-year federal prison sentence. Investigators say the couple were in contact with a purported buyer who turned out to be an FBI informant.