TAMPA — A tip from Facebook led to the arrest of a Tampa man accused of recording himself having sex with a young girl and using the social media site to send pornographic photos and videos, authorities said.Dabbs Postma, 44, was arrested Friday and charged with sexual assault of a child 12 years or older, promoting the sexual performance of a child and possession of child pornography.The investigation began when Facebook alerted the National Center for Missing and Exploited Children to hundreds of pornographic photos and videos sent between two users between Aug. 4 and Oct. 25, according to a Hillsborough County Sheriff’s Office arrest report.Investigators learned the girl was enrolled in a Hillsborough County public school. Detectives used a subpoena to track the IP address for Postma’s Facebook username, the report states. At least one of the videos showed Postman performing a sex act on the girl.On Friday, sheriff’s deputies and Tampa police officers arrived with a warrant to search Postma’s home. They found a video showing him performing sex acts on the girl, and Postma admitted to producing child pornography and having a sexual relationship with the girl in North Carolina and Tampa, the report states. Postma was already on probation at the time of his arrest and is being held without bail in the Hillsborough County jail.Records show Postma has a lengthy arrest record in Florida with previous convictions for felony domestic battery, illegal possession of a firearm, misdemeanor fraud and habitually driving without a valid license.Times senior news researcher Caryn Baird contributed to this report. Contact Tony Marrero at [email protected] or (813) 226-3374. Follow @tmarrerotimes.