Story highlights A US Navy plane spotted three stranded mariners Thursday after seeing their makeshift sign

The three mariners had been on the remote, uninhabited Pacific island for three days

Washington (CNN) The U.S. Navy and Coast Guard rescued three mariners from a remote, uninhabited Pacific island Thursday after a Navy plane spotted palm fronds spelling the word "help" on the sand.

The castaways who constructed the makeshift S.O.S. had been stranded on Fanadik Island for three days, according to the Coast Guard. This island lies about 2,600 miles southwest of Honolulu.

Their small vessel had been swamped by a large wave and the sailors were forced to swim two miles to shore at night, Chief Petty Officer Sara Mooer, a spokesperson for the Coast Guard, told CNN.

The Coast Guard was notified that the three men were missing Tuesday morning.

The remote island is part of the Federated States of Micronesia, which is comprised of more than 600 islands. The Coast Guard carries out search and rescue operations for the region due to a lack of local capacity.

A US Navy P-8 Poseidon like the one that spotted the castaways' sign (GREG WOOD/AFP/Getty Images)

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