(SEOUL, South Korea) -- A U.S. Marine helicopter made a "hard landing" while conducting a routine flight in South Korea on Tuesday, the military said.
In a statement, United States Forces Korea said 21 personnel, including five crew members, were aboard the Marine CH-53E Super Stallion helicopter when it down. All passengers were sent to a nearby hospital for treatment.
Fifteen personnel have since been released, according to the military; the six remaining are in stable condition.
The downed helicopter was taking part in the Foal Eagle training exercise, the military drills being conducted between the U.S. and South Korea. The military said a "comprehensive investigation" will take place to determine what caused it to make a hard landing.
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