A West Point cadet who heroically attempted to assist a struggling swimmer on a Long Island beach died Friday, after spending four days on life support.

Thomas Surdyke, 18, was at Southampton Beach on June 24 with a fellow cadet when he and an acquaintance were caught by a riptide, according to the family’s GoFundMe Web page.

Surdyke, a Festus, Mo., native, nearly drowned trying to help the other swimmer and was eventually pulled from the water by rescuers.

Emergency crews revived Surdyke on the beach but lost his heartbeat three times on the way to the hospital. Brain damage suffered during the incident proved devastating, and Surdyke passed away four days later, according to his family.

The other swimmer survived.

Surdyke had just completed his first year at West Point and would have turned 19 on the Fourth of July.