On the anniversary of the xenophobic Pegida movement — which stands for patriotic Europeans Against the Islamisation of Europe — 3,000 supporters of an offshoot group, Legida, gathered in the eastern city of Leipzig to show their anti-immigrant stance.
Meanwhile, a group of 250 people, described by police in Leipzig as "hooligans" rampaged through the city torching cars and smashing windows and pledging to fight so-called "sex jihad." Others waved German flags and held placards depicting Angela Merkel wearing a veil.
"These Muslim gangs declared war on us at the same time in Cologne, in Hamburg, in Stuttgart, in Bielefeld and other cities," Tatjana Festerling, member of Pegida told reporters.
"Under no circumstances should we dismiss these attacks, these harbingers of a sex jihad on women, as an isolated case. No, there's more to come, that was only the start."
"This is an alarming signal, which we are taking very seriously," a spokesman for Leipzig police said.
German ministers are calling for calm, warning people not to take the law into their own hands.
"As abominable as the crimes in Cologne and other cities were, one thing remains clear: there is no justification for blanket agitation against foreigners," justice minister Heiko Mass said.
According to German media, Slovakia's Prime Minister Robert Fico said migrants had become a "protected species" in Germany.
Fico has called for an emergency meeting of EU leaders to discuss tighter border controls following the Cologne attacks. Meanwhile, the Polish government said it will refuse to take in young male asylum seekers.
