German leaders on Sunday paid respects to the victims of the July 22 mass shooting in Munich and sought to calm a public unsettled by a series of attacks.

But behind the show of unity, political fault lines exposed by the recent run of violence widened over the weekend as Chancellor Angela Merkel’s Bavarian allies attacked her migrant policy and alleged she wasn’t taking Germans’ security concerns seriously enough.

German President Joachim Gauck, speaking at a memorial event in Bavarian Parliament in Munich on Sunday, listed the first names of the shooting’s largely teenage victims, of six different nationalities: Armela, Can, Chousein, Dijamant, Giuliano, Janos, Sabine, Selcuk, and Sevda. Authorities have described the shooter, who took his own life after killing nine, as an 18-year-old Iranian-German dual national who appears to have harbored far-right views.

Mr. Gauck also alluded to the two terrorist acts by migrants that occurred within days of the Munich shooting and raised the specter of a new wave of Islamist terrorism in Germany, a country that had been spared the large-scale attacks seen in neighboring Belgium and France.

“If mass shooters and terrorists have something in common, it is likely alone the intention to rob our feeling of security and normality,” Mr. Gauck said. “But there is one thing we will not give either the mass shooters and attackers or the terrorists: our submission.”

Mr. Gauck is Germany’s head of state, but his position is largely symbolic. Ms. Merkel, who runs the government, sat in the audience during the memorial but didn’t speak.

She had interrupted her summer vacation on Thursday to hold a news conference in Berlin in the wake of the attacks, telling journalists that she remained confident in her “We can do it” mantra for Germany’s handling of the refugee crisis.

“We have already accomplished a great deal in the last 11 months,” Ms. Merkel said Thursday, referring to a period in which hundreds of thousands of people seeking asylum streamed into Germany. “Therefore we will also manage the new challenge now in front of us, the one described by the term ‘Islamist terror.’”

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