Pangala was killed in a road accident around midnight on May 14 while he was returning home from Mulooru near here, on his two-wheeler. Though the incident initially passed off as an accident further probe revealed it to be a planned murder.
Police had earlier arrested three persons in this connection but the main accused is still at large, police sources said.
A large number of women and fish merchants belonging to the Mogaveera community participated in the protest. Rajiv Kanchan, president of Mangalore Hadinalku Patna Mogaveera Samyuktha Sabha, Vasudev Salian, Yathish Baikampady, deputy mayor Kavitha and several other leaders of the fishermen community were present.