BERLIN (Reuters) - Germany has launched a probe into the leak to far-right groups of an arrest warrant against an Iraqi suspect in a stabbing case that triggered two days of violent anti-immigrant protests.

Riot policemen stand guard as the right-wing supporters protest after a German man was stabbed last weekend in Chemnitz, Germany, August 27, 2018. REUTERS/Matthias Rietschel

Interior Minister Horst Seehofer said judicial authorities should use all means at their disposal to respond to the leak of the warrant for the arrest of the 22-year-old Iraqi suspect over the fatal stabbing of a 35-year-old German man.

The death sparked violent anti-foreigner protests in the eastern city of Chemnitz.

The leak of the warrant was a highly unusual occurrence that drew sharp criticism across Germany, which has strict privacy guidelines for judicial proceedings, and raised concerns of possible links between police and anti-migrant parties.

Critics said the warrant, which contained details of the number of stab wounds, may have been leaked to further inflame anger against migrants.

The stabbing and subsequent protests have exposed deep divisions in German society over Chancellor Angela Merkel’s 2015 decision to open the door to more than one million migrants, mostly Muslims fleeing Middle East conflicts.

The incident has also laid bare close links between a range of anti-migrant groups, including soccer hooligans and the Alternative for Germany (AfD) party, and their ability to quickly mobilize thousands of demonstrators.

Prosecutors on Wednesday said they had launched an investigation into the leak and had taken steps to protect two witnesses named in the document.

The deputy premier of the state, Martin Dulig, a Social Democrat, suggested in two German media interviews that the leak had likely come from police or judicial authorities. “We have a bigger problem to deal with there,” he told broadcaster MDR.

A spokesman for the Dresden prosecutor’s office, which is handling the investigation, said the circle of those who had access to the document was not small.

ANTI-MIGRANT RIOTS

Neither the Iraqi, nor a second suspect arrested in the stabbing, a 23-year-old Syrian man, had engaged an attorney, making it unlikely the leak came from them, experts said.

Saxon police last week apologized for a separate incident involving an off-duty police employee at an anti-Islam rally.

The AfD and PEGIDA, a far-right group that is under observation by intelligence agencies, say they will march again in Chemnitz on Saturday to “mourn Daniel H. (the stabbing victim) and the others killed by Germany’s forced multiculturalisation.”

PEGIDA co-founder Lutz Bachmann was among the first to publish the arrest warrant on Tuesday evening, along with a group called “Pro Chemnitz” and a local AfD politician.

Fifty-seven percent of Germans view the anti-migrant riots, during which at least 10 people raised their arms in the banned “Hitler salute”, as a danger to democracy, a new Civey poll showed.

Ninety percent of AfD backers did not see the protests as a threat to democracy, it showed.

AfD leader Alexander Gauland justified the anti-migrant riots as self-defense in an interview with Die Welt newspaper. “When a homicide like this occurs, it’s normal that people flip out. Self-defense is certainly not vigilante justice.”

Merkel and her cabinet discussed the situation during a cabinet meeting on Wednesday and underscored their opposition to any form of vigilance justice, Seehofer told reporters. Such actions were “completely unacceptable.”

But U.N. human rights chief Zeid Ra’ad al-Hussein called for more widespread denunciation of what he called “shocking” images from Chemnitz. “We really need a concentration of voices now to say that when we have incitement to hatred this is prohibited under international human rights law,” he told reporters.