Turkish Airlines said it had fired 211 employees over suspected links to US-based preacher Fethullah Gulen and behaviour "conflicting with the interest of our country" in the wake of last week's coup.
The flag carrier said their contracts were terminated due to "the non-fulfillment of performance criteria and in line with the necessary actions we are taking against the FETO structure, attitudes and behaviour conflicting with the interest of our country and company".
The authorities accuse 75-year-old Gulen of running a group it labels the Fethullah Terror Organisation (FETO) that was behind the coup, and Ankara has demanded that Washington extradite him.
Earlier, Turkey ordered the detention of 42 journalists, broadcaster NTV reports.
A purge since the coup has targeted more than 60,000 people, drawing fire from the European Union. The arrests or suspensions of soldiers, police, judges and civil servants in response to the July 15-16 putsch have raised concerns among rights groups and Western countries, who fear President Tayyip Erdogan is capitalising on it to tighten his grip on power.
The preacher - who lives in a secluded compound in rural Pennsylvania and whose foundation runs a global network of schools, charities and media interests - has strongly denied the accusations against him.
In a statement signed by the airline's media relations unit, Turkish Airlines stressed that it stands "united with all of the heroic and honourable Turkish people" against the coup plotters' "malevolent illegal attempt".
"Under any circumstances, we have and will continue to fulfil our responsibility to contribute to democracy."
EU Commission President Jean-Claude Juncker questioned Ankara's long-standing aspiration to join the EU. "I believe that Turkey, in its current state, is not in a position to become a member any time soon and not even over a longer period," Juncker said.
Juncker also said that if Turkey reintroduces the death penalty - something the government has said it must consider, responding to calls at public rallies for the coup leaders to be executed - it would stop the EU accession process immediately.
- AFP, AP