EU aviation authorities warn airlines of 'possible launch of air strikes into Syria' The alert said air strikes were possible within 72 hours of when it was issued.

Europe’s air traffic control agency on Tuesday told airlines operating over the eastern Mediterranean Sea to exercise caution due to possible military action in Syria.

The alert, issued by the European Aviation Safety Agency, warned of a potential air strike into Syria within the next three days, though the agency did not detail where the air strike would originate.

“Due to the possible launch of airstrikes into Syria with air-to-ground and / or cruise missiles within the next 72 hours, and the possibility of intermittent disruption of radio navigation equipment, due consideration needs to be taken when planning flight operations in the Eastern Mediterranean / Nicosia FIR area,” the EASA’s notification said, referring to the airspace above that region.

The warning comes as the U.S. and its allies continue to review intelligence and weigh retaliatory options over the suspected chemical attack on Saturday that has since affected about 500 people in Douma, according to the World Health Organization.

President Donald Trump, before a cabinet meeting on Monday, told reporters to anticipate “major decisions over the next 24 to 48 hours.” He then appeared to fire a warning on Wednesday to Russia, Syria’s ally, tweeting: “Russia vows to shoot down any and all missiles fired at Syria. Get ready Russia, because they will be coming, nice and new and ‘smart!’ You shouldn’t be partners with a Gas Killing Animal who kills his people and enjoys it!”

The Federal Aviation Administration has prohibited civil flights by U.S.-registered aircraft, pilots and operators over the region since 2014.

“The FAA finds that this action is necessary to safeguard against continuing hazards to persons and aircraft engaged in such flight operations,” the rule states.

As of 7:08 p.m. UTC, four commercial aircraft were flying above Syria according to flight tracking website FlightRadar24: Two were operated by Syrian Air, one by Iraqi Airways and one by Qatar Airways.