A petrol bomb exploded outside the hotel where India's president was staying in Bangladesh on Monday as four more protesters died in a wave of violence sparked by the prosecution of local Islamist leaders.
Police in the capital Dhaka and hotel employees said nobody was injured by the explosion just outside the luxury Sonargaon Pan Pacific Hotel where President Pranab Mukherjee was staying.
"We suspect the cocktail was hurled from a moving vehicle," Biplob Sarker, a senior policeman in Dhaka, told AFP, while Mukherjee's office called it a "minor explosion".
The violence came as four more protesters were killed in clashes in the south and northwest as protests continued to rage over the conviction of the leaders of Islamist party Jamaat-e-Islami by a local war crimes court.
A total of 81 people have been killed since the first conviction on January 21, with sixty-five of the deaths since the vice-president of Jamaat-e-Islami Delwar Hossain Sayedee was sentenced to hang last Thursday.
Jamaat-e-Islami leaders are on trial at the domestic International Crimes Tribunal, accused of colluding with Pakistan and pro-Pakistan militias during the country's war for independence in 1971.
The worst violence in impoverished Bangladesh since independence comes ahead of elections due in the next 12 months and it has already hit the country's economy, which the central bank says was already slowing down.
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 crippled the country again on Monday.
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.
Paramilitary border guards in the southern town of Kolaroa shot dead three 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.
As part of their protests, the supporters of Jamaat have blockaded 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.
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.