Police fire water cannons at a street festival in Hamburg, Germany.
German demonstrators have clashed with police officers and damaged public property after an all-night street festival in the city of Hamburg.

On Saturday, police had detained approximately 30 protesters who caused property damage and fought with law enforcement, AFP reported.

Police fired water cannons to subdue left-wing demonstrators who were pelting officers with stones, bottles and firecrackers, as well as setting ablaze barricades.

Rioters had also caused property damage by attacking a bank, setting fire to cars and burning garbage containers.

Patrons had attended the annual Schanzenfest street festival which attracts large crowds with its music and food stalls, and often ends in clashes between protesters and police.

About 2,500 police officials had prepared beforehand and participated in this year's melee.