Arsonists set fire to at least nine buses in different parts of the capital during the by-polls to the Dhaka-18 constituency.
The assailants carried out the attacks in the guise of passengers between 12:00pm and 4:30pm Thursday, said Dhaka Metropolitan Police spokesman Walid Hossain.
Police have collected security camera footage to identify the attackers and get to the masterminds behind the incidents, he said.
Fire Service official Russel Sikdar said the firemen doused all the flames. None was injured, he added.
The first incident took place at Naya Paltan following a march by BNP activists to protest against alleged irregularities in the by-election. The torched vehicle was owned by the National Board of Revenue.
The arsonists later set fire to a Rajanigandha Paribahan Ltd bus near the National Press Club. They set fire to another bus owned by state-owned Agrani Bank and a BRTC double-decker at Motijheel.
The rest of the buses were set ablaze at Shahbagh, Gulistan, Naya Bazar, Paltan and Bhatara.
The arson attacks are connected to the by-election, said Walid, the deputy commissioner of media at the DMP.
There were no disruptions to traffic, he added.
Electronic voting started in the Dhaka-18 constituency comprising wards 1, 16, 43 to 54 under the Dhaka North City Corporation and Airport area at 8:00am on Thursday.
Police have arrested three people after several crude bombs exploded outside the Malekabanu Adarsha Bidyaniketan voting centre in Uttara.
"Police found several other bombs," said DMP Deputy Commissioner (Uttara Zone) Md Shahidullah.
"No violence took place inside the school," said Returning Officer GM Sahtab Uddin.
The blasts occurred hours after the BNP candidate SM Jahangir Hossain had visited the polling station to cast his vote. The Awami League candidate Habib Hasan went there after the incident, reports bdnews24.com.
