The Coast Guard has stopped searching for an overdue medical aircraft the disappeared near the Alaskan village of Kake.

Before halting the search at 5:30 p.m. local time on Thursday, Coast Guard crews in the air and on the sea had spent 63 hours combing an area that sprawled across 240 square nautical miles of the Alexander Archipelago.

On Wednesday, Alaska Wildlife Troopers spotted aircraft debris near the south tip of Admiralty Island in the Chatham Strait.

Coast Guard officials said that it appears to be wreckage from the twin-engine Guardian King Air 200 medical flight that was due to land at the village of Kake at 6:19 p.m. Tuesday but never made it.

Officials said no other aircraft debris has been located.

“Suspending a search for any reason is one of the most difficult decisions we have to make,” said Capt. Stephen White, Sector Juneau’s commander, in a statement emailed to Navy Times. “This was an extensive search effort in some very challenging conditions."

In the wake of the Coast Guard announcement, Randy Lyman, Senior Vice President of Operations for Guardian Flight, issued a statement thanking the armed forces, state agencies and local citizens who joined the search for the lost plane.

“While the formal search and rescue effort has been discontinued and we recognize the gravity of the situation, we will continue efforts to recover our friends in order to hopefully reunite them with their beloved families,” Lyman said.

“Our hearts are heavy, and we respectfully offer our deepest thoughts and prayers to our lost employees and their families. We will miss pilot Patrick Coyle, flight nurse Stacie Rae Morse, and flight paramedic Margaret Langston. This tragedy is dreadful for everyone as they were our friends and neighbors.”

Lyman grounded Guardian Flight’s fleet of aircraft on Wednesday morning and vowed to cooperate with probes launched by the National Transportation Safety Board and the Federal Aviation Administration into the cause of the mishap.

The plane had been scheduled to retrieve a patient from Kake, a hamlet located about 635 miles southeast of Anchorage on the northwest shore of Kupreanof Island.

Coast Guard cutters Anacapa and Bailey Barco and MH-60 Jayhawk rescue helicopters from Air Station Sitka and Air Station Kodiak spearheaded the search for the missing aircraft but they were joined by the Alaska Army and Air National Guard, Alaska State Troopers, Alaska Marine Highways Ferries, the Anchorage Air Route Traffic Control Center and search and rescue teams from Kake, Petersburg and Wrangell.

“Good Samaritans” — a flotilla of boats from commercial operators and local residents — also assisted in the hunt but they were unable to find Coyle, 63, Morse, 30, or Langston, 43.