The Marines were not seriously hurt, officials told NBC News, but several dealt with smoke inhalation. Some showed symptoms consistent with concussions, including headaches, raising concern about possible traumatic brain injuries among the crew.
Officials have not released the identities of the Marines or the name of the ship involved. The attack adds to a run of tension in the Strait of Hormuz, a waterway that carries a large share of the world's oil shipments and sits at the center of ongoing friction between the U.S. And Iran.
For the families of those Marines, the injuries mean a wait for more clarity on their long-term health, especially with brain injury symptoms that can take time to fully surface. Military leaders face fresh pressure over how U.S. Forces operate in one of the most contested shipping corridors on the planet.
No death toll came out of the attack.