Dhaka, Jan. 24 -- At least 11 houses have been vandalised, three set on fire, and more than 500 crude bombs exploded during attacks in Shariatpur Sadar, allegedly triggered by a dispute over joining the Bangladesh Nationalist Party (BNP).

The incident took place around 11pm on Friday in Chargayghar village of Shulpara Union, said Chikandi Police Outpost chief Md Golam Rasul.

According to locals, the violence followed the recent joining of Shulpara Union Parishad Chairman Abdul Mannan Khan Bhasani, a former Awami League leader, and 20 to 25 of his supporters into the BNP.

The move reportedly angered a rival BNP faction.

The joining took place on Jan 17 during a prayer gathering organised in memory of former prime minister Khaleda Zia a...