State authorities say they've arrested a federal agent in Central Texas for using the Internet to arrange a sexual tryst with an underage girl.
    
The attorney general's office announced Friday that 50-year-old Forrest William Johnson was charged with a felony count of online solicitation of a minor.
    
Johnson worked in law enforcement for U.S. Customs and Border Protection at Austin-Bergstrom International Airport.
    
Authorities say Johnson posted an explicit online advertisement and was contacted by an undercover officer posing as a 15-year-old girl. He was arrested Wednesday when he arrived for the encounter.
    
The Austin resident posted a $20,000 bond Thursday. If convicted, he faces two to 10 years in prison and up to a $10,000 fine.
    
Williamson County jail records did not indicate an attorney representing Johnson.