The U.S. Coast Guard suspended Thursday at sundown a massive search for two firefighters who disappeared during a fishing trip off the coast of Florida, officials said at a Thursday news conference.

The announcement came on the seventh day of the search for Fairfax County firefighter Justin Walker and Jacksonville, Fla., firefighter Brian McCluney, which has covered more than 105,000 square miles of Atlantic Ocean and has drawn national attention.

Coast Guard Capt. Mark Vlaun said the chances of finding Walker and McCluney alive had dwindled and the area to search had grown too large with the drift of ocean currents potentially carrying the boat anywhere from Florida to New England, where vessels searched off the coast Thursday.

“At this point in time, without additional information, we have simply reached a point where our computer modeling and our ability to search in a given location are no longer allowing us to search with any reasonable degree or probability of success,” Vlaun said.

Walker’s family did not immediately reply to a request for comment, but an official with the Fairfax County firefighters’ union said he expected volunteers to continue searching despite the long odds. The search drew dozens of volunteers in boats and aircraft, as well as an outpouring of funds to support the effort.

“We are hoping for a miracle,” said Eric Villman, secretary and treasurer of the International Association of Firefighters Local 2068. “It would be completely on brand for Walker to show up with no help from anyone else.”

Family members were optimistic after the discovery of a tackle bag belonging to McCluney about 50 nautical miles off the coast of St. Augustine, Fla., on Monday, but hopes have gradually faded after rescuers found no other debris that might focus their efforts.

It remains unclear what befell the boaters. The pair did not issue a distress signal or warn of any problems before they disappeared. The weather was mostly good, besides a band of thunderstorms that swept the area the afternoon of Aug. 16. McCluney’s wife speculated in interviews that the boat may have broken down, which it had done before.

The friends launched their 24-foot boat from Port Canaveral, which is near the Kennedy Space Center on Florida’s central Atlantic Coast on the morning of Aug. 16. They had planned to go to a fishing spot called reef “8A” and return by 6 p.m., a trip that was meant to honor McCluney’s recently deceased father, family members said.

When the firefighters had not returned by 8 p.m., family members notified the Coast Guard, and the search began. The search included dozens of boats and multiple aircraft from local, state and federal agencies, including the Navy and Customs and Border Protection.

Villman said he sat next to Walker for six months in recruit school for the Fairfax County Fire Department, calling him industrious and easy to work with.

“Walker was the type of guy people would want to be a firefighter,” Villman said.

Villman said he didn’t take Walker’s disappearance seriously at first because his colleague is a consummate outdoorsman and adventurer. He expected Walker to show up soon enough with a story to tell.

Villman said Walker and his wife are campsite minders near the Shenandoah Valley and he is an avid motorcyclist. Walker is originally from Florida, but he moved to the D.C. area to take a job with the Fairfax County Fire Department, where he has worked for seven years.

Walker is a master technician at the Franconia fire station. Villman said he was an expert in the operations of firetrucks.

McCluney is a decorated Navy veteran who is married and has two children.

Villman said he was appreciative of the work of the Coast Guard and the volunteers.

“It’s incredible what people did for him, but it’s a sad day,” Villman said Thursday. “Today’s a sad day.”