Police have fired plastic baton rounds and used water cannon after coming under attack from loyalists in Belfast city centre ahead of a republican parade.
Officers were pelted with bottles, fireworks and glasses as hundreds of loyalist demonstrators gathered to protest at the rally.
Metal guttering ripped from shop fronts was also used in the violence.
Two police officers have been hospitalised after the initial clashes, said a PSNI spokesperson.
Protesters have attempted to block part of the route that the Anti-Internment League parade is due to take later this evening.