A three-member panel of judges of Bangladesh's International Crimes Tribunal led by Justice Anwarul Haque pronounced the judgement as two of the convicts appeared on the dock while six others were tried in absentia as they were on the run to evade justice.
The verdict came as the prosecution accused all the eight of five charges relating to crimes like mass murders, abductions, tortures and lootings.
Prosecution lawyers said six of the convicts were members of Al-badr auxiliary force of the Pakistani troops during the war and carried out atrocities in northern Jamalpur district.
The two others belonged to Razakar, another Bengali-manned armed group raised by Pakistanis during the war.
Manned by activists of fundamentalist Jamaat-e-Islami, which was opposed to Bangladesh's 1971 independence from Pakistan, the Al-Badr appeared as an extremely notorious force by carrying out ruthless atrocities siding with Pakistani troops.
The verdict came amid a nationwide tension following the recent two back-to-back Islamist terror attacks in the country following which Prime Minister Sheikh Hasina hinted that Jamaat could be behind the assaults.
Bangladesh has so far executed four war crimes convicts since the process began to try the top Bengali perpetrators of 1971 atrocities in line with the electoral commitment of Prime Minister Hasina in 2008.
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