A Wantagh man was sentenced to 28 years in prison on Monday after pleading guilty to child pornography and sexual assault charges for abusing a toddler.

Christopher Bertsch, 38, was convicted in the U.S. District Court in Central Islip by Eastern District Judge Joanna Seybert after pleading guilty in November 2020 to child sexual exploitation.

Prosecutors said Bertsch molested an 18-month-old toddler and filmed sex acts to share with others. Authorities said he ran an online chat room where he instructed other adults on how to sexually abuse children. Bertsch allowed people into his chat room, “requiring photographic evidence with a minor under their control.”

“Today’s sentence removes a dangerous predator who not only abused minors and created videos of them, but horribly also operated a chat room where he instructed adults on how to abuse minors and create and share footage of it,” the Eastern District Attorney in the United States said. Breon Peace said in a statement. “The FBI’s exceptional undercover work made this prosecution possible. I urge parents and guardians to encourage their children to tell a trusted adult if someone asks them to engage in inappropriate behavior.”

Bertsch must also register as a sex offender upon his release from prison, authorities said, and have no unsupervised contact with minors.

Police from the Long Island Child Exploitation Task Force issued a search warrant in February 2020 at Bertsch’s home with his wife, after discovering he was sharing videos in a chat room he called Kik, according to a criminal complaint.

Police say Bertsch shared child pornography with an undercover officer in the chat room. Police seized his collection of child pornography, “including dozens of videos and hundreds of images of child pornography showing him engaging in sex with children,” prosecutors said.

His attorney could not immediately be reached for comment.

U.S. Attorney officials said the case was brought before Project Safe Childhood, made up of U.S. Marshals and state and local officials who help prosecute individuals for child exploitation and rescue children from sexual abuse and child pornography.