A US Navy sailor was sentenced on Friday to a year in prison for taking photos of classified areas inside a nuclear attack submarine while it was in port in Connecticut.

Kristian Saucier, of Arlington, Vermont, appeared in federal court in Bridgeport, where a judge also ordered him to serve six months of home confinement with electronic monitoring during a three-year period of supervised release after the prison time. He pleaded guilty in May to unauthorized detention of defense information and had faced five to six years in prison under federal sentencing guidelines.

Saucier admitted to taking six photos of classified areas inside the USS Alexandria in 2009 when it was in Groton and he was a 22-year-old machinist mate on the submarine. The photos showed the nuclear reactor compartment, the auxiliary steam propulsion panel and the maneuvering compartment, prosecutors said.

Saucier took the photos knowing they were classified, but did so only to be able to show his family and future children what he did while he was in the Navy, his lawyers said. He denied sharing the photos with any unauthorized recipient.

“It was a foolish mistake by a very young man,” his lawyer, Greg Rinckey, said after the sentencing. “It’s a very sad case because Kristian Saucier is a fine young man. We don’t believe this was really his true character.”

Saucier is expected to receive an “other than honorable” discharge from the Navy next month, Rinckey said. He is to report to prison on 12 October. Saucier did not speak during Friday’s court proceeding.

Federal prosecutors said the FBI and the Naval Criminal Investigative Service were never able to determine if the photos had been distributed to unauthorized people because Saucier destroyed key evidence including his laptop computer, a camera and a memory card after an interview with the FBI in 2012.

Prosecutors asked US district judge Stefan Underhill to send Saucier to prison for five years, saying his conduct put national security at risk.

Kristian Saucier is a fine young man. We don’t believe this was really his true character.

The investigation began in 2012 when a waste station supervisor in Hampton, Connecticut, found Saucier’s cellphone with the submarine photos on top of a pile of demolition trash and showed it to his friend, who was a retired Navy chief and brought the phone to the NCIS, according to court documents.

Saucier, who grew up in Cape Coral, Florida, had asked Underhill to sentence him to probation. In court filings, he compared his case to Democratic presidential nominee Hillary Clinton’s use of a private email server when she was secretary of state. The FBI declined to charge Clinton for her handling of classified information while using the server.

Saucier’s lawyers also said two other Alexandria crew members were caught taking photos in the same locations as Saucier, but were not prosecuted, only disciplined by the Navy.