Dec. 12 (UPI) — The U.S. Department of Transportation has fined a pair of foreign airlines $825,000 for operating flights in prohibited airspace while using other carriers’ designator codes, the department announced Thursday.

U.S. authorities fined Etihad Airways $400,000 for using United Airlines designator code and Ethiopian Airlines $425,000 for using the code that belongs to JetBlue Airways.

“Ethiopian Airlines operated a significant number of flights carrying the United Airlines code between Ethiopia and Djibouti in airspace prohibited by the FAA to U.S. operators,” the Transportation Department officials said in a statement.

The department’s consumer affairs office said Ethiopian violated the law between February 2020 and December 2022. Some of the violations occurred even after officials announced they were conducting an investigation into the carrier’s practice.

“By operating these flights in this manner, Ethiopian Airlines violated the conditions of its authority to operate and engaged in air transportation without the proper DOT authority,” the release continued.

Etihad operated flights between the United Arab Emirates and the United States in airspace prohibited by the FAA to U.S. operators using JetBlue’s code between September 2002 and April 2023, the department said.

Ethiopian Airlines and Etihad Airways were both ordered to cease and desist from future violations.