PITTSBURGH » A Pittsburgh man has been indicted on charges he stalked and harassed an FBI agent, who had once investigated him, by posting a fake Craigslist sex ad that included the agent’s phone number and address.

The interstate stalking charge against 47-year-old Frederick Banks was unsealed this week. A federal magistrate has ordered Banks jailed until trial.

Authorities say the agent investigated Banks before he was sentenced to five years in prison for a 2003 case in which he sold bogus and pirated computer software online.

Authorities say Banks sought retribution by posting the ad in June on a Craigslist site for the Tampa, Florida, area. The ad says the agent and his wife were seeking a male for sex. Two people responded to the ad.

Banks’ attorney didn’t immediately comment Wednesday.