Story highlights Crude bombs, tear gas and gunfire rock Dhaka

At least four people were killed in Sunday's protests

The government calls on protesters to leave; leaders say they're staying

The Islamists want Bangladesh to adopt laws against blasphemy, along with other demands

The streets of Bangladesh's capital rang with the sound of gunfire, explosions and tear-gas canisters Sunday as Islamist protesters demanding laws against blasphemy battled police, leaving four dead.

Tens of thousands of supporters of the Hefazat-e-Islam movement blocked nearly all the roads leading into the capital, Dhaka, as they pressed a list of demands, including the anti-blasphemy statute. Clashes broke out when Hefazat activists tried to break a police cordon.

Street battles went on for hours, with police firing rubber bullets and tear gas and the Islamists hurling crude explosives and chunks of brick. At least three bodies were left in the streets, and one more person was reported dead at a hospital. Police said scores of people were hurt, including police officers and journalists.

Syed Ashraful Islam, secretary-general of the ruling Awami League and a government minister, said demonstrators set fire to the Communist Party of Bangladesh office and ransacked several other business establishments in Purana Paltan in central Dhaka.

Islam warned that the government would go tough if did not end its program and leave Dhaka peacefully. But at a rally in the evening, Hefazat leaders said they would not leave the capital until their demands were met.

Shahriar Shahid, the managing editor of the state-run news agency Bangladesh Sangbad Sanghstha, said the service had to suspend operations for the day after Hefazat activists set a fire at the entrance of its office.

"They didn't enter the office, but they also didn't allow us to go to the office," Shahid said.

The protest was unrelated to the recent building collapse that killed hundreds of people and sparked demonstrations and clashes as well.

Sunday's demonstrators called for tough laws against bloggers and writers who they believe insult the Prophet Mohammed. A similar demonstration in February left four other people dead.

Hezafat's call for an anti-blasphemy law is aimed at a group of bloggers, online activists and authors they have called "atheists" and accused of denigrating Islam and Mohammed. Online activists who had a pioneering role in organizing the Shahbagh sit-in have denied they are atheists.

The bloggers launched a sit-in campaign at Dhaka's Shahbagh Square in February, demanding a ban on Bangladesh's largest Islamic party, Jamaat-e-Islami. They have also called for the death penalty for Jamaat-e-Islami leaders convicted of war crimes charges that date back to 1971, when Bangladesh won its independence from Pakistan. The party opposed independence.

Sunday's Hefazat protesters said they wanted the government to meet 13 demands, including the reinstatement of "absolute trust and faith in the Almighty Allah" in the constitution and capital punishment for those who would denigrate Islam and its prophet.

The list also includes mandatory Islamic education, bans on the free mixing of men and women and on the public installation of sculpture and a declaration that Ahmadiyya Muslim sect is non-Muslim.