A former school security guard has been arrested for alleged possession of child pornography and sex acts with a minor.

Sean Coraggio, 22, of Shirley, was arrested at his home Tuesday morning. Prosecutors say Coraggio engaged in sex acts with a person under 17 years of age. They would not reveal the age or gender of the alleged victim.

Prosecutors say when they arrested Coraggio, he was in possession of "several hundred pictures" of children engaged in sex acts. Sources told News 12 that the alleged child pornography included videos with boys under 16 years old.

Coraggio is a U.S. Marine reservist, a volunteer at the Mastic Ambulance Corp and has no criminal record. He previously worked for Summit Security at Stony Brook University. He recently trained to work security in the Longwood School District. Officials say he only appeared for two days of training and did not return.

Coraggio also worked for 14 hours as a freelance security guard at William Floyd High School. A spokesman said they stopped calling him when he didn't finish the necessary civil service exams.

The 22-year-old is held on $60,000. He's due back in court on Friday.