FBI agents have arrested a Bradenton man they say tried to gain access to children for sex by posting and answering Craigslist ads for babysitting.

Nathan Alexander Bryan, 39, who also lived in Orlando while he was being investigated, was arrested June 21 and charged with attempted enticement of a minor, the FBI said Monday.

Investigators with the FBI Child Exploitation Task Force say that over the last 14 months, Bryan posted advertisements offering babysitting, nanny and housekeeping services to gain access to children.

"Apparently, he put information in where he was actually posting his services online a babysitter, a nanny and a housekeeper, and the investigators on that task force quickly realized he was doing this to gain access to children," said Spec. Agent Dave Couvertier, FBI Tampa Office.

According to the criminal complaint, an undercover agent posted an ad indicating he was a single dad who was looking for a male babysitter to watch his 8-year-old stepson.

The agent assumed the undercover profile of a "bad dad" in his 40s who was looking for a man to engage in sex acts with his 8-year-old stepson in the Bradenton-Sarasota area. The complaint says Bryan responded to the ad and left his phone number.

"Between April 2014 and June 2015, Bryan made several SMS communications [i.e. text messages] to me, believing I was the stepfather of the young boy and discussed his traveling to the designated location to meet the child who he believed was between 8 to 9 years of age to engage in sexual activity with the child," the agent wrote in the report.

According to the 15-page arrest affidavit, text message exchanges between the agent and Bryan included the following:

AGENT:  Ok good. So we r clear just between you and stepson ok
BRYAN: Who else would be involved
AGENT: Just making sure u understand. Had others wanted me to be involved while they were with my stepson jst not into that don't want to complicate things.
BRYAN: I don't care either way.

According to the agent, Bryan communicated on June 18, 2014 that he had moved to Orlando, but would be coming back to the area. He was back in Bradenton early this month when the Bradenton Police Department received an email from him saying he had been robbed. The FBI was alerted to the email, and the agent re-initiated contact.

The complaint states that on June 21, Bryan traveled to an agreed-upon location in Bradenton "with the intent to engage in illegal sexual acts with a person Bryan believed to be a minor."

"I knew Nathan had kids of his own and he seemed like a cool guy," said neighbor Justin Rodrequez. "He talked to everybody. Never thought he'd be in prison. Federal prison."

Bryan was arrested at that location. He made a court appearance June 22 and was detained without bond.

Investigators are asking that anyone with information about the case or who may have hired Bryan for childcare services to contact the FBI Tampa Field Office at 1-866-838-1153.