Schools and businesses were shut Monday across Bangladesh on the second day of a general strike called by Islamist protesters, as three more demonstrators died in the deadliest violence since independence.

Police said the three were killed in clashes in the south and northwest in continued protests over the conviction of Islamist leaders for war crimes, raising the overall toll to 80 since January 21.

Sixty-four of the total have died since the vice-president of Jamaat-e-Islami, the nation's largest Islamic party, was sentenced to death Thursday.

Paramilitary border guards in the southern town of Kolaroa shot dead two people as a group of around 1,000 protesters tried to attack them with sticks and bricks, local government official Hossain Shawkat told AFP.

In the northwestern town of Ullapara, a protester died on the way to hospital after police fired on hundreds of Islamists demanding a halt to the war crimes trials.

Violent clashes erupted across the impoverished country after Jamaat's vice-president and firebrand Islamic preacher Delwar Hossain Sayedee became the third Islamist to be sentenced by a domestic tribunal.

Sayedee was found guilty of murder, religious persecution and rape during the 1971 independence war against Pakistan. Jamaat says the process is an attempt by the ruling party to settle scores and not about delivering justice.

The verdicts and the ensuing violence prompted Jamaat to call a two-day nationwide strike that began Sunday and has virtually crippled the country.

Schools and businesses were shut nationwide on the second day of the strike. The main road between the capital Dhaka and the second city Chittagong was virtually deserted, as were other inter-city highways.

Security has been strengthened throughout the country, particularly in Dhaka where around 10,000 police and members of the elite Rapid Action Battalion were on duty Monday.

As part of their protests, the Islamists have blockade a highway leading to the popular Cox's Bazaar tourist region, where several hundred holidaymakers have been trapped including some foreigners.

District police chief Azad Miah told AFP that while more than 3,000 tourists had been able to leave since Thursday, mostly through the local airport, around 700 remained stranded.

Police said the latest clashes were fuelled by rumours that images of Sayedee's face were reflected off the surface of the moon, leading many Islamists to assert that he was innocent.

"Some imams have used this rumour to mobilise villagers against police," said police inspector Shamsul Haq.

The government has banned rallies and gatherings in at least four towns in the north to quell violence, police said.

The war crimes trials of a dozen leaders from Jamaat and the main opposition Bangladesh Nationalist Party have opened old wounds and divided the nation, with the opposition accusing the government of staging a witch-hunt.

The government, which says the 1971 war claimed three million lives, rejects the claims and accuses Jamaat leaders of being part of pro-Pakistani militias blamed for much of the carnage during the war.

Independent estimates put the death toll from the war at between 300,000 and 500,000.