A tribunal has sentenced to death the leader of an Islamic political party over his role in murder and atrocities during the nation’s 1971 war of independence. The decision triggered violence and clashes across the country that left at least 30 people dead.

The war crimes tribunal found Delwar Hossain Sayedee, a leader of Jamaat-e-Islami, guilty on eight of 20 counts involving mass killings, rape and other offences committed during the nine-month war against Pakistan. The savage war left around three million people dead, while 200,000 women were raped. Millions fled to India.

According to the Associated Press, prosecutor Syed Haider Ali declared after the verdict: “Justice has been done to those who lost their loved ones at the hands of Sayedee.”

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Sayedee, 73, is the third defendant to be convicted of crimes against humanity since Prime Minister Sheikh Hasina’s government established the war crimes tribunal in 2010.

Last month, Abdul Quader Mollah was sentenced to life in prison on similar charges while in January the court sentenced former Jamaat leader Abul Kalam Azad to death. A further seven senior leaders of the party are yet to be dealt with by the court.

The tribunal and its work has underscored faultlines within Bangladeshi society. Jamaat-e-Islami, the largest Islamic party in Bangladesh, campaigned against the independence war more than 40 years ago but has always denied it was involved in atrocities.

It is an ally of the Bangladesh Nationalist Party, the main opposition party. Both the BNP and Jamaat said the trial was politically motivated and was intended to damage the opposition before elections this year or early in 2013.

Today, with Jamaat-e-Islami enforcing a nationwide general strike to protest against the trial, the party and its student wing clashed with police and security forces. Hindu temples were targeted and The Daily Star newspaper reported that at least 32 people were killed and dozens more injured.