Booking photo of Michael Bradley. St. Petersburg Police Department

A concerned Florida mother used an innovative plan to help nab an adult man who was sending her 11-year-old daughter pornographic text messages.

When the mother contacted Florida authorities about the photos, officers informed her that more evidence was needed to arrest him, reports ABC

Her daughter had friended the suspect, Michael Bradley, 23, through a Facebook account she set up. She then gave him her phone number, according to both police and the child's mother.

Bradley began texting the girl for the next few weeks, with his messages to her soon becoming increasingly graphic in nature. This included asking the girl if she was still a virgin and if she would skip class to meet with him, police say.

"It got out of control very quick, just out of control," the mother, who asked not be identified to protect her daughter, told WFTS-TV.

After being confronted by the mother, who called him and asked him to no longer contact her daughter, Bradley denied the allegation and blamed the woman's daughter for writing the messages, say police.

Even with copies of the texts and Bradley's number, the fact that they didn't have enough evidence to prove he was actually sending the messages left police in a tough spot when the mother went to authorities for help.

"Just because someone texts something inappropriate doesn't mean there's sufficient evidence for an arrest," St. Petersburg, Fla., police spokesman Michael Puetz told ABC "First, we have to establish the suspect is the person sending that text. Just because it's a particular phone number doesn't suffice. You need more evidence."

This led the mother to devise her own scheme to trick Bradley and prove he sent the messages. She said she simply wanted to "take the extra steps to make sure my child is safe."

The mother began texting Bradley as though she was her daughter. He asked her for a photo and she then texted him a picture of a teen girl from a Target advertisement.

The mother says he then sent the image of "a whole naked body." But without anything to identify who actually sent the image, police told her there was still nothing that could be done.

The mother then asked for a picture of Bradley's face, a photo that, once received, "changed the dynamic" of the case, Puetz said.

"Now we could identify the individual and make an arrest," he said.

Bradley was arrested on Monday and charged with 16 counts. These include distributing obscene material to a minor.

The mother just wishes that police would have been able to do more sooner.

"I think it should have been acted on more quickly," she said.

Bradley will return to court on Friday. He is being held on $120,000 bail reports KTNV-TV.