Chowdhury Mueen Uddin, who now lives in London, and Ashrafuzzaman Khan, who lives in New York City, were tried in absentia by a court in Dhaka, Bangladesh, The New York Times reported.
A judge ruled the men "encouraged, gave moral support to, and participated in the killing" of 18 people, including university professors, journalists and physicians, who supported Bangladesh's independence from Pakistan, and sentenced the defendants to death by hanging.
The death sentences will be carried out after the defendants are arrested or surrender, the tribunal chief said.
This was the ninth verdict by Bangladesh's two war crimes tribunals, The (Dhaka) Daily Star reported.
The tribunals have sentenced five other people to death this year and three people to life in prison.
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