A U.S. Air Force F-15C Eagle fighter jet crashed into the North Sea off the coast of England on Monday, the Air Forces' 48th Fighter Wing confirmed.
The jet, deployed from Royal Air Force Base Lakenheath in eastern England, northeast of London, crashed at about 4:40 a.m. Eastern.
"At the time of the accident, the aircraft was on a routine training mission with one pilot on board," the 48th Fighter Wing said in a brief statement, adding that the cause of the crash remained unclear.
In a video statement provided by the U.S. military, Colonel Will Marshall of the 48th Fighter Wing said later Monday that the pilot was "still missing."
"We will provide updates as they become available, while prioritizing respect and consideration for the pilot's family," Marshall said.
The Air Force said a British search and rescue team had been called to support the efforts to find the pilot.
BBC News quoted a spokesperson with the U.K. Coastguard as saying one helicopter and two lifeboats had been sent to the area, about 90 miles off the coast of East Yorkshire, to help with the search.
The Coastguard said other vessels were heading to the area to help, too, after hearing the agency's mayday call.
Hours before the crash, RAF Lakenheath posted a photo to the base's twitter account showing F-15s in flight, saying the 48th Fighter Wing was ready to "take on Monday."
First published on June 15, 2020 / 6:13 AM
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Tucker Reals is the CBSNews.com foreign editor, based at the CBS News London bureau.