German police have arrested a 28-year-old Syrian man in the northern port city of Hamburg on suspicion of planning an Islamist attack, police and prosecutors announced on Tuesday.

His brother, who is four years younger and lives in Kempten near the Austrian border in the southern state of Bavaria, is suspected of having aided and abetted in the planning of the alleged attack, according to the Federal Criminal Police Office, the Hamburg Criminal Police Office and the Hamburg Public Prosecutor’s Office.

German investigators said that an Islamist extremist motivation for last week’s fatal knife attack in Wuerzburg appears likely, but they have not so far found any propaganda or other extremist material.

They also plan more checks on the suspect’s mental health.

Friday’s assault in and outside a store in the centre of the Bavarian city left three women dead and another six people seriously injured.

The suspect, a 24-year-old Somali man, was shot in the leg by police and arrested after people surrounded him and tried to hold him at bay with chairs and sticks.

Officials have said they believe the suspect was a lone assailant.

He was sent to jail on Saturday pending a possible indictment.

Bavarian extremism and terrorism investigators took over the case on Saturday because an Islamist background appears likely, Munich prosecutors and Bavaria’s state criminal police office said in a statement.

They said that is supported by witnesses’ account that he twice shouted “Allahu akbar”, the Arabic phrase for “God is great”, and also referred to “jihad” after his arrest.

Investigators are still evaluating objects that were seized at his accommodation, including two mobile phones, but have not yet found signs of propaganda or extremist material, they added.

They also plan to order a psychiatric evaluation of the suspect to determine whether he can be held criminally responsible for his actions and whether he needs to be sent to a psychiatric hospital or rehabilitation clinic.

Prosecutors have said there were two incidents earlier this year that resulted in him being sent briefly to a psychiatric hospital.

Read more: Woman, 18, arrested in France over plot to target church

Police in Germany’s southern state of Bavaria are investigating two officers suspected of performing the illegal Hitler salute.

The German constitution makes it a crime to exhibit Nazi symbols and the incident is likely to feed into a heated debate about racism and the rise of the far right after a record influx of mainly Muslim migrants three years ago.

Police said in a statement on Saturday the two policemen had shouted anti-immigrant remarks and made the salute in a pub in the city of Rosenheim on Thursday. It based its information on a witness who was in the same beer garden as the two officers.

A third man, described as a security guard in the police statement, had also taken part and made the salute. The policemen have been suspended.

German politicians have been urging action to combat a rise in hostility toward foreigners after skinheads last Sunday clashed with police in an eastern city where a man was fatally stabbed and two migrants were identified as the main suspects.

Skinheads raised their arms in Nazi salutes, chased people who appeared to be outsiders and wrestled with police in Chemnitz after police identified the suspects as a Syrian and an Iraqi.

The leaking of the arrest warrant for one of the two stabbing suspects to the anti-Islam group PEGIDA raised concerns that some justice officials in the state of Saxony, where Chemnitz is located, were sympathetic to the far right.

“We will not allow the extreme right to infiltrate our society,” Justice Minister Katarina Barley told the Bild am Sonntag newspaper on Sunday, urging authorities in Saxony to investigate far-right groups.

Chancellor Angela Merkel’s liberal immigration policy remains deeply divisive in a country that has taken in more than 1.6 million people over the last four years.

The influx contributed to the rise of the Alternative for Germany (AfD) party, which entered parliament for the first time in an election last year with a campaign that proclaimed Islam to be incompatible with the German constitution.

Some 8,000 people took part in a demonstration organised by the AfD and the anti-Islam group PEGIDA in Chemnitz on Saturday. About 3,000 people attended a rival protest by leftist groups.

Police said on Sunday that the demonstrations were largely peaceful.

Leftist groups will hold a concert in the city on Monday to denounce xenophobia and hatred against refugees and foreigners.

New Interior Minister Horst Seehofer said Islam does not belong to Germany and set out hardline immigration policies in an interview published on Friday, as he sought to see off rising far-right challengers.

Seehofer told Bild newspaper he would push through a “master plan for quicker deportations”, in his first major interview since he was sworn into office on Wednesday.

The minister – a member of Chancellor Angela Merkel’s CSU Bavarian allies who are further to the right than her own Christian Democrats (CDU) – said he would also classify more states as ‘safe’ countries of origin, which would make it easier to deport failed asylum seekers.

The statements come after Merkel’s conservatives, and their coalition allies – the Social Democrats – lost ground to the anti-immigrant Alternative for Germany (AfD) party in elections last year.

Seehofer is particularly keen to show his party is tackling immigration ahead of Bavaria’s October regional election, when the AfD is expected to enter that state assembly.

“Islam does not belong to Germany,” Seehofer said, contradicting former German president Christian Wulff who fuelled a debate over immigration in 2010 by saying Islam was part of Germany.

In 2015 Merkel echoed Wulff’s words at a time when anti-immigration campaign group PEGIDA – or Patriotic Europeans Against the Islamisation of the West – was holding marches.

“LIVE WITH US”

“Of course the Muslims living here do belong to Germany,” Seehofer said before going on to say Germany should not give up its own traditions or customs, which had Christianity at their heart.

“My message is: Muslims need to live with us, not next to us or against us,” he said.

The government estimates between 4.4 and 4.7 million Muslims are living in Germany. Many of them have a Turkish background and many of the more than a million migrants who have arrived in the country from the Middle East and elsewhere after Merkel adopted an open-door policy in mid-2015 are also Muslims.

Andre Poggenburg, head of the AfD in the eastern state of Saxony, said Seehofer was copying his party with a view to Bavaria’s October regional election: “Horst Seehofer has taken this message from our manifesto word for word,” he said.

The far-left Linke and Greens condemned Seehofer’s message, and the Social Democrats’ Natascha Kohnen told broadcaster n-tv: “Saying that incites people against each other at a time when we really don’t need that. What we really need is politicians who bring people together.”

In a coalition agreement, Merkel’s CDU/CSU conservative bloc and the Social Democrats agreed they would manage and limit migration to Germany and Europe to avoid a re-run of the 2015 refugee crisis.

They also said they did not expect migration (excluding labour migration) to rise above the range of 180,000 to 220,000 per year.

An Italian newspaper has been criticised for distributing free copies of an annotated version of Hitler’s “Mein Kampf” with a paid supplement to Saturday’s edition.

Prime Minister Matteo Renzi said on Twitter that Il Giornale’s decision to give away the copies of the Nazi leader’s political treatise was “squalid” and expressed solidarity with Italy’s Jewish community.

Efraim Zuroff, director of the Israeli office of the Simon Wiesenthal Center, was quoted as telling Corriere della Sera it was unprecedented for a newspaper to use “Mein Kampf” to boost sales, while the ANSA news agency quoted Israeli Embassy sources as expressing surprise.

But Il Giornale, a centre-right daily owned by the family of former premier Silvio Berlusconi, said the decision to distribute the edition of the text, which includes critical notes by an Italian historian, aimed “to study what is evil to avoid its return.”

Acknowledging the controversy in an editorial, editor-in-chief Alessandro Sallusti said nobody could suspect the move to be an apology for Nazism and the global Jewish conspiracy posited in the book written between 1924 and 1926.

“The concerns of our friends of the Italian Jewish community, who always have and always will see us by their side … deserve all our respect,” Sallusti wrote.

Il Giornale on Saturday started selling an eight-volume history of the Third Reich, with the annotated copy of Mein Kampf free for readers who buy the first volume.

A 70-year copyright on Hitler’s book held by the state of Bavaria expired at the end of 2015, prompting Munich’s Institute for Contemporary History to re-issue it as an annotated version earlier this year in an effort “to thoroughly deconstruct Hitler’s propaganda”