A Seattle teacher appeared in a federal courtroom Wednesday where he was charged with possession of child pornography.

According to charging documents, Gabriel Cronin, a science teacher at Seattle Academy, used a school laptop computer to obtain and view explicit images of children.

Seattle Academy placed Cronin on leave Monday and said in a statement that the safety and well-being of students is a top priority. The school says it does not believe any current or former student has been the subject of inappropriate conduct related to Cronin.

Cronin led the school's robotics program and occasionally traveled with students and other staff.

According to investigators, Cronin admitted to loading pornography onto his cellphone for a school trip to Zambia.

Cronin said he never inappropriately touched kids, but told investigators that he fantasized about students he works with.

Cronin's cousin reported his behavior to the National Center for Missing and Exploited Children after Cronin admitted to family members that he had been viewing child porn for years and said he had an addiction.

Investigators later confiscated Cronin's computer and found several galleries of female children, many of them nude.

Cronin's attorney, Brad Meryhew, who represents people accused of sex crimes, declined to comment to KING 5 after Wednesday’s court appearance.

Cronin remains in custody and will be back in court next Tuesday for a hearing to determine whether he stays in custody or gets released on bond. He faces up to 20 years in prison.