A special war crimes court in Bangladesh has sentenced four men to death for killing, torture, arson and looting during the nation's independence war against Pakistan in 1971.

The ruling Tuesday is likely to aggravate the divide between moderates and extremists in the Sunni-majority nation, which is grappling with a wave of deadly assaults targeting atheist writers, religious minorities and political activists.

The court, accused by rights groups of holding flawed proceedings, said the four were involved in the deaths of nine people. Only one suspect, Shamsuddin Ahmed, was in court for the verdict. Authorities are still hunting for the other three: Gazi Abdul Mannan, Hafiz Uddin, and Shamsuddin Ahmed's brother, Nasiruddin.

The three-judge tribunal also sentenced a fifth man, Azharul Islam, to life in prison on two murder charges.