A row has broken out about whether Eurowings flight 4U2904, scheduled to fly from Stuttgart to Ankara on Saturday, was annulled because the pilot was too scared to fly to Turkey.

Photos posted to Facebook showed disgruntled passengers at a Eurowings counter in Stuttgart after being informed that their flight would not be taking off. Airport police called to the scene are also seen in the images.

The official explanation issued by the airline at 1:30 a.m. (2330 UTC) on Sunday was that the flight was canceled because of a "sudden sickness of a crew member." Eurowings confirmed that information in an email statement to DW.

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"Eurowings flight 4U2904 was annulled because one of the pilots called in sick," the airline wrote. "Because this happened at short notice, it was unfortunately not possible to activate a replacement pilot for this flight."

The airline added that it has flown to Turkey 55 times this month and that Saturday's was the only cancellation during this period.

But those affected tell a different story. The brother of one of the passengers said that airline personnel had said the flight was canceled because of the pilot's political concerns. Another passenger told German public broadcaster ARD that she had been told the same thing.

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Some people are now calling for travelers to shun the airline.

"It's high time to recognize that these measures are aimed not just at Turkey (which is bad enough) but Turkish people in the EU," wrote a political activist who recently converted to Islam on Facebook. "Rise up and boycott companies like this."

Last week, in response to Ankara's jailing of journalists and human rights activists, the German government changed its travel advisory to warn German citizens of "risks" associated with travel to Turkey. Pilots who work for Lufthansa, Eurowings' parent company, are allowed to declare themselves "unfit to fly," if they feel they are unable to correctly discharge their duties.