Two children and seven other people were burned alive when protesters hurled petrol bombs at packed vehicles overnight up to Saturday, in the latest attacks in Bangladesh, which have brought the toll to 70 in a month of violence.
Opposition activists attacked a packed Dhaka-bound bus in Gaibandha district in the north on Friday night, killing six passengers, including two children.
Three people were killed in a similar firebombing on their truck in the southern district of Barisal on Saturday morning, Reuters reported. A number of people were critically injured in the two attacks.
Earlier this week, seven people were killed in their sleep when petrol bombs were hurled at a bus in Chuddogram.
Protests heralded by Opposition leader Khaleda Zia have turned deadly over the last month, and firebombings on vehicles has become a common form of arson.
Zia called for protests and nationwide blockade of roads and railways as she builds pressure on Prime Minister Sheikh Hasina to announce a fresh general election.
The Opposition had boycotted the January 2014 polls claiming that they were rigged.
More than 800 vehicles have been firebombed as protests grew violent last month, though Zia claims that neither her Bangladesh Nationalist Party (BNP) nor its Islamist allies had called for such violence.