– German authorities unveiled a new memorial in Berlin on Tuesday, honoring the 12 people killed in the terrorist attack at a Christmas market last year.

Before the ceremony, Chancellor Angela Merkel joined members of the acting government, President Frank-Walter Steinmeier and representatives from Berlin at a memorial service open only to attack survivors and the victims' families. Berlin Mayor Michael Müller ­dedicated the memorial in Breitscheid Square.

It was a year to the day that the attacker, Anis Amri, drove a stolen truck into the crowded square, killing 12 people and injuring dozens. Amri, who died in a shootout with the Italian police days after the attack, had been under scrutiny by German security for months before, but repeated opportunities to deport him were missed.

On Tuesday, Steinmeier offered an apology for the shortcomings of the German state and promised those present that their "complaints and warnings have not fallen on deaf ears."

But it was the concessions from the chancellor, who met on Monday for the first time since the attack with several dozen people who lost ­family members or were injured, that many victims had waited to hear. Earlier this month, they complained in an open letter that German authorities, and Merkel specifically, had badly mishandled the events leading up to the attack and afterward.

For a leader who has been called the "Teflon chancellor" for her ability to emerge unscathed from difficult situations — including disputes with European leaders over the debt crisis in the eurozone — the complaints this time appeared to hurt. Months after an inconclusive election in September that was largely viewed as a rebuke of her open-door refugee policy, Merkel has appeared more vulnerable politically than she has at any time in her 12 years in office.

Standing before the memorial steps that bear the names of the victims, Merkel appeared visibly shaken.

"Today is a day of mourning," Merkel told reporters, "but also a day of concerted determination to improve."

She described her meeting Monday as "very open and blunt," adding that it "revealed the weaknesses that our government showed in such a situation."

New York Times