A man is behind bars in Lowndes County after police say he has allegedly threatened to ambush and rape female real estate agents around the state.

Police were familiar with Frank Mainka, 44, of Scott County. He is a convicted sex offender with a record of cyberstalking that dates back almost 15 years. He’s currently jailed on charges of cyberstalking in Lowndes and Lamar counties, as well as failing to register as a sex offender in Scott County.

Earlier this month, though, a realtor in Lowndes County contacted the Sheriff’s Department to report some phone calls she’d been receiving. She said the calls and text messages she had gotten described violent and graphic things he wanted to do to her, according to WCBI.

Mainka allegedly told the real estate agent he would have his wife set up an appointment to view a home, and that he would be there to rape her. As the agent spoke with police, Mainka allegedly called her again. The deputy was able to listen to the conversation.

An investigation into social media and phone data brought investigators to Mainka as their suspect. The brought in the Mississippi Bureau of Investigation on the case.

Mainka told police that he has threatened women like this before but nobody ever came forward, so police are asking that if anyone has been one of his alleged victims in the past, they should come forward to possibly aid in the investigation.

Mainka is in the Lowndes County Jail on a $100,000 bond.

Other victims or those with information on Mainka are asked to please call the sheriff’s department at (662) 328-6788 or Golden Triangle Crime Stoppers (800) 530-7151.