Dhaka, Bangladesh (CNN) -- Outraged by a court verdict they considered too lenient, thousands of people took to the streets across Bangladesh on Wednesday demanding the death penalty for an Islamic party leader convicted of war crimes carried out more than four decades ago.
"We've taken additional measures across the country to heighten security," State Minister for Home Affairs Shamsul Hoque told reporters.
The demonstrations began Tuesday, when an International Crimes Tribunal sentenced Abdul Quader Mollah, assistant secretary general for the Jamaat-e-Islami party, to life in prison.
The Jamaat-e-Islami party had called for a two-day general strike across Bangladesh beginning Tuesday, and demonstrators clashed with police and demanded that ruling party officials scrap the trial process.
The government on Tuesday evening called in paramilitary troopers to maintain law and order in Dhaka and elsewhere as deadly protests erupted after the verdict.
Jamaat-e-Islami protested the verdict as demonstrators -- including some from ruling party alliances -- took to the streets demanding the death penalty for Mollah.
"We've deployed troopers from the Border Guards of Bangladesh to maintain law and order," Hoque said.
Hundreds of Dhaka University students took to the streets in the capital's Shahbagh Square, where they were joined by other city residents in protests that began Tuesday.
Home Ministry officials said security forces were patrolling in Dhaka and other major cities, including in the large southeastern port city of Chittagong, where at least four people were killed Tuesday during clashes between police and supporters of Jamaat-e-Islami.
Police opened fire and shot tear-gas shells to disperse the protesters, who torched and otherwise damaged more than 100 vehicles in major cities.
Jamaat-e-Islami said its members would continue to protest; many of its leaders are behind bars facing charges of murder, arson, looting and rape stemming from the war of independence in 1971.
They said the war-crimes trials, which began after more than 40 years of independence, was done with "ill political motive."
Prime Minister Sheikh Hasina showed no sign of backing down, saying the trials would be completed at any cost.
The government, which promised in its election pledges in 2008 to complete the war-crimes trials, set up the tribunals in 2010.
Amid tight security, a three-member panel of judges of the International Crimes Tribunal-2 delivered the judgment against Mollah in a crowded courtroom on Tuesday.
Mollah, 64, was found guilty of five of six charges, including murder.
They included crimes against humanity, tribunal Chairman Justice Obaidul Hassan said.
After the verdict was read, Mollah stood from the chair on which he had been seated and cried, "Allahu Akbar!" (God is Great!)
He declared he was innocent and began to curse the judges and the government.
He then pulled a copy of the Quran from his pocket and held it in front of him, saying that the judges would one day find themselves on trial in accordance with the holy book's law.
Lawmakers of the ruling party alliance criticized the verdict in parliament and asked the prosecution to appeal for the death penalty.
Mollah, who was the chief of the students' wing of Jamaat-e-Islami in 1971, is the first Jamaat-e-Islami leader convicted in a war-crimes case by the tribunal.
On January 21, the same tribunal sentenced to death the first war crimes convict, Abul Kalam Azad, alias Bachchu Razakar.
Bangladesh had been the eastern portion of Pakistan until it gained independence in 1971 in a war that killed 3 million people.