A case has been filed over a fire at the '36 July' memorial arch in Tungipara, Gopalganj, naming 75 accused persons.
Tungipara police chief Md Ayub Ali confirmed the case.
Imon Islam filed it at Tungipara police station on the night of August 5.
Police said the complaint names 35 people and includes 40 unidentified persons as accused.
Among those named is Sajedur Rahman Sohan, described by police as a joint general secretary of the Tungipara Upazila Chhatra League.
The memorial arch was erected on the evening of August 1 near Gate No. 1 of Sheikh Mujibur Rahman's mausoleum.
Police said the Tungipara municipal units of Chhatra Dal and Swechchhasebak Dal built it to commemorate people killed and injured during the July uprising.
Police said unidentified people set the arch on fire late that night and left the area.
The lower section of the structure was partially burned, police said.
Ayub Ali said police operations to arrest the accused were continuing.