Germany will not tolerate "vigilante justice," Chancellor Angela Merkel's spokesman said on Monday, after hundreds of far-right protesters staged a violent demonstration in response to a fatal stabbing that authorities blamed on a Syrian and an Iraqi.

Sunday's protest in the eastern city of Chemnitz was the latest manifestation of unrest since Merkel's government allowed about 1 million asylum seekers to enter Germany in 2015, triggering a shift to the right in German politics.

Television news channels broadcast amateur footage of skinheads chasing a foreign-looking man through the streets. Other clips showed hundreds of demonstrators shouting "We are the people!" a slogan used by far-right supporters.