The Purbadhala upazila AL office was also ransacked, allegedly by BNP activists.

Witnesses and police said several hundred party activists, led by Purbadhala AL President Warasat Hossen Belal Birpratik brought out a procession at the upazila headquarters in the morning.

Local BNP activists led by party lawmaker Mohammad Ali also brought out a procession as part of its Independence Day programme.

As the processions faced each other in front of the local AL office, a clash ensued following chanting of slogans and exchange of hot words, witnesses said.

Among the injured, AL leader and former Union Parishad chairman Hasnat Jaman Khokon was sent to Mymensingh Medical College Hospital (MMCH) in a critical condition.

Some witnesses claimed that police did not resist when BNP activists first attacked the AL procession.

The attackers also ransacked AL office while police looked on.

The BNP activists later swooped on some shops at Purbadhala bazar and looted goods.