The union also has suspended its Surja Sen Hall unit, which was apparently behind the attack, bdnews24.com reported.
BCL president H.M. Badiuzzaman Shohag and general secretary Siddiki Nazmul Alam announced the decision in a statement Monday night, hours after the attack.
The activists allegedly beat up seven journalists over a game of football at the university primises.
The injured were Jamuna TV reporter Monirul Islam, Asian TV's Arafat Sarkar Setu, The Report's Zahid Hasan, Manabkantha's Reza Akash, and former reporters of Somoy TV, Independent TV and banglanews24.com's Masudur Rahman, Galib Sharif, and Mahmudul Hasan respectively.
Manabkantha reporter Reza said members of the DU Journalists Association went to the Mal Chattar area in the campus Monday evening to take part in a friendly football match to celebrate the FIFA World Cup final.
"Students of Surja Sen Hall, who were playing there, left the field after we requested them," he said.
"Minutes later, a group of 30-35 students from the hall brandishing sticks and machetes attacked us," Akash claimed.
A witness said Mizan and Sohagh, both second-year students of political science and international relations, had led the attack.