SARTELL -- A Park Rapids man faces felony charges after he was accused of sending sexual messages to a 13-year-old Sartell girl.

According to the criminal complaint 54-year-old Calvin Bird Jr. starting talking to the girl back in September after she posted a question on the social media site Whisper.

Police say the two began sending text messages, with several conversations becoming sexual.

Authorities began investigating the case and began to pose as the girl. While undercover, police say Bird started sending nude photos of himself and asking her if she would masturbate while they text.

Bird was arrested on Monday. Police say he admitted to having sexual conversations with the girl and knew she was 13-years-old.

He faces charges of eight counts of engaging in electronic sexual contact with a minor.