As this publication reported last night, United States European Command (EUCOM) announced that a U.S. aircraft had crashed in the Eastern Mediterranean. However, moments ago EUCOM confirmed that five U.S. service members died in the crash after initially withholding the status of the crew. The official announcement reads below.
This publication reported that a U.S. Navy Search and Rescue helicopter was combing the area East of Cyprus. That search seems to have found the aircraft and reported the deaths of the personnel.