Two chief pilots from Turkey’s flag carrier died from the novel coronavirus this week, according to the head of Turkey Civil Aviation Labor Union.

Ali Kemal Tatlibal offered condolences to Serdar Gundogdu and Mehmet Ali Kilic in a tweet that said the pilots died at hospitals during treatment for the virus that has killed 1,403 people in Turkey and infected more than 65,100.

Turkish Airlines, which has taken steps to stem the spread of COVID-19 in Turkey, extended the suspension of international flights Tuesday until May 20.

After originating in Wuhan, China last December, the virus has spread to

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