DHAKA – A Bangladesh war crimes court Sunday sentenced a British-based Muslim leader and a US citizen to death in absentia for murder, in the latest ruling over atrocities during the war of independence.

London-based Chowdhury Mueen-Uddin and Ashrafuzzaman Khan, from the United States, were found guilty by the International Crimes Tribunal of 11 charges related to the kidnap and slaughter of 18 intellectuals during the 1971 conflict.

"Justice will not be done if they are not awarded capital punishment," senior judge Obaidul Hassan told the packed court in Dhaka.

Prosecutors accused the pair, who fled Bangladesh after it gained independence from Pakistan, of being "high command" members of the notorious Al Badr militia that supported Pakistani forces during the war.

"They killed top professors, journalists and doctors to make the nation devoid of any talent," senior prosecutor M.K. Rahman told reporters outside the court after the ruling.

The pair refused to return to Bangladesh to face trial, but their tribunal-appointed lawyers denied the charges against them. No defence witnesses were called during the trial held earlier this year.

The tribunal has now convicted 10 people, mostly leaders of the country's largest Islamic party the Jamaat-e-Islami, for war crimes, with seven of them sentenced to death by hanging. At least another eight are on trial.

The trials have sparked protests throughout the Muslim-majority country, leaving at least 150 people dead since January when the court started handing down their verdicts.

Jamaat claims the trials are politically motivated and accuses the secular government of trying to execute its entire leadership.

The government says the trials are needed to heal the wounds of the conflict.

The latest sentences are unlikely to trigger a backlash in the volatile country since both men, aged in their 60s, left the country years ago and have started new lives in London and New York.

During the final days of the war, when it became clear Pakistan was losing, intellectuals were rounded up and murdered in what was the most brutal chapter of the nine-month struggle.

The pro-Pakistani militias, wanting to deprive the new Bangladeshi state of an intellectual elite, captured writers, university professors and others. Many of their bodies were later found dumped in marshes and flood plains outside the capital with their hands tied.

Masuda Faruq Ratna broke down in tears in court after the ruling. Ratna, a prosecution witness, said she saw the pair along with others kidnap her uncle, a professor, from Dhaka University.

"I was 17 when they took my uncle. Now I am 58 and the two are sentenced to death. I hope I'll live long enough to see the two brought to the country and executed," she told AFP.

Several hundred people, who had gathered in a central Dhaka square, cheered the ruling and staged a celebratory procession.

Mueen-Uddin has held positions in a host of top Islamic organisations in Britain and was involved in setting up the Muslim Council of Britain – the country's largest umbrella group representing Muslims.

He was a newspaper reporter in what was then East Pakistan when the war broke out.

On his website before Sunday's sentence, Mueen-Uddin said that although he opposed Bangladesh's independence at the time, he was not involved in any crimes.

He said he had "no confidence that I will receive a fair hearing in a tribunal already accused of judicial and procedural misconduct".

There was no immediate reaction to the sentence from Mueen-Uddin. Britain historically has refused extradition requests if the conviction carries a death sentence.

Khan was a Dhaka University student leader during the war and is now believed to be living in New York. Prosecutors have described him as the "chief executor" for the Al Badr militia. He has yet to make public statements on the allegations.

The government set up the court in 2010 to try collaborators, but rights groups including Human Rights Watch have said its procedures fall short of international standards.

The government says up to three million people were killed in the war, while independent researchers put the number between 300,000 and 500,000.