Say it ain’t so, Marine.

Kyle Carpenter, the youngest-ever living recipient of the supreme and unparalleled award for American military valor, the Medal of Honor, is now in major hot water, facing a serious criminal charge.

Police in Columbia, South Carolina, where the former decorated Marine is attending school at the University of South Carolina, has formally charged him with “hit-and-run”.

This from Maxim:

Sometime in early December, Carpenter … was allegedly involved in an automobile accident in which he made an improper left turn, striking a pedestrian who was crossing the street, according to The State. After checking to make sure the person was uninjured, he apparently got back in his car and took off. After checking surveillance tapes, police identified the automobile as Carpenter’s.

Drugs or alcohol are not thought to have been a factor in the accident. The hit-and-run charge has been classified as a misdemeanor.

As we’ve documented many times on this blog, Carpenter earned the MOH for an unimaginable act of courage while serving in Afghanistan in 2010: during a Taliban attack, he dove in front of a live grenade to protect one of his fellow Marines. He survived, but suffered catastrophic injuries to his body, including wounds to his face and arm.

Stay tuned for more details on this still-developing story.