Unidentified persons lobbed three bombs at the vehicle of Local Government Minister Syed Ashraful Islam in Tongi, on the outskirts of Dhaka, while four petrol bombs exploded at the residence of Commerce Minister G M Quader.
Islam's car was attacked around 8:30 am when he was going to visit his constituency in Kishoreganj to submit his nomination papers.
He escaped unhurt as the bombs missed the target, the Daily Star reported quoting witnesses.
The main opposition BNP and its rightwing allies have extended by two days a 72-hour nationwide strike demanding the postponement of the polls.
The campaign, scheduled to end tomorrow, virtually paralysed the country for the second straight week, even as the death toll in two weeks of political violence rose to 28.