The Coast Guard called off the search for a Dallas resident on Saturday.

Bruttus Walter, 24, was apparently pulled away by currents off the coast of Rincon, Puerto Rico. He is still missing as of Wednesday.

He was last sighted swimming at Steps Beach in Rincon, Puerto Rico, Fox reports. He was reportedly a strong swimmer but was carried away and last seen struggling in the water.

One other person nearby survived the currents and made it safely to shore after receiving assistance from a bystander, who reported the incident to 911.

The Coast Guard, along with other emergency units, including the Puerto Rico Emergency Management Agency and Puerto Rico Police Joint Forces of Rapid Action, searched a total of 742 square nautical miles for Walter but eventually called off the search, according to a press release from the U.S. Coast Guard.

In a combined effort, the rescue agencies and Coast Guard conducted 26 air and surface searches of the surrounding area.

“Despite our best efforts to find him, the fate of this young man remains unknown,” Commander Beau Powers, Sector San Juan chief of response, said in the press release. “Our thoughts and prayers are with the family and [we] hope they can find strength during this most difficult time.”

“I’d like to extend my appreciation to all the Coast Guard units and the rescue teams from our local partners in the Puerto Rico Police and Puerto Rico Emergency Management Agency for their tireless efforts and support in this case,” Powers continued.

The search lasted for three days. First responders initially received a phone call from a witness regarding the emergency.

A Coast Guard MH-60 Jayhawk Helicopter was used as part of the search, as was the Coast Guard Cutter Joseph Tezanos, a 154-foot coastal patrol boat homeported in San Juan, Puerto Rico.