The U.S. Coast Guard rescued four people from a partially sinking boat south of Dry Tortugas National Park in the Florida Keys Monday. One of the rescued people had to be airlifted for treatment.

Rough seas and storms led to the listing. An emergency beacon aboard the boat called on the Coast Guard for help, and air and sea crews reacted fast, reaching the vessel shortly after midnight, the military service said in a release.

A helicopter lowered a rescue swimmer into the water, whereupon he reached the boat and found that one of the people on board needed emergency medical treatment.

Given the rough seas and storm, a direct flight from the listing boat wasn’t possible. All four people rode a small boat to the Coast Guard cutter Charles David Jr., from which one of the quartet was flown to Lower Keys Medical Center in Key West. The other three returned to Key West aboard the cutter.

None of the people rescued were identified by authorities.

“We were fortunate to be able to rescue four people and bring them to shore safely today. These were extremely challenging conditions to conduct a rescue operation in. … Four lives were saved today … because the mariners had an emergency position indicating radio beacon onboard that pinpointed the distress location,” Coast Guard Sector Key West Commander Capt. Jason Ingram said.

The boat did not fully sink and remains adrift, the Coast Guard said.

The boat is called the Viejo Cangrejo, the Coast Guard said in a Facebook post, without adding what type of vessel it is.

• Brad Matthews can be reached at bmatthews@washingtontimes.com.