Riots that raged for hours just a mile from the Group of 20 meeting site left German officials struggling to explain over the weekend how protests that had long been predicted spiraled out of control.
Only after SWAT teams, riot police and water cannons swept block by block were authorities able to end the riots early Saturday morning in the left-leaning Schanzenviertel neighborhood, a 20-minute walk from the venue where leaders of the world's 20 largest economies met.
Stores were looted, barricades and cars set on fire, and officers attacked with rocks, bottles and slingshots, Hamburg police said. Authorities moved to quell the riots late Friday night only after they had raged for hours, according to several shopkeepers in one of the hardest-hit streets. Unrest continued, to a smaller degree, on Saturday night, as more barricades and vehicles burned in the streets.
A police spokesman said intelligence suggesting some of Friday night's roughly 1,500 rioters were preparing to pelt authorities from buildings with cobblestones and Molotov cocktails had caused the delay in stopping the unrest. "We had prepared for the G-20 summit to be attacked, not the people of Hamburg," Hamburg police spokesman Timo Zill told ZDF public television.
The riot in the Schanzenviertel Friday night appeared to be the most violent flare-up as tens of thousands of people protested across the city. By Sunday, 411 people had been detained and 476 officers injured, according to the police. An unspecified number of protesters were also injured.
Hamburg's Interior minister, Andy Grote, on Saturday said the riot had been long-planned -- to a degree "we have never witnessed before" -- and that many of the perpetrators were still in the city. Mr. Grote sought to justify the time it took for police to move into the Schanzenviertel. "We wanted to ensure that by moving it, we wouldn't put our colleagues' lives at risk and that we would win the upper-hand," he said.
German politicians had warned of possible violence for months, in part because the summit was held near two of the more radical neighborhoods in a city long a hub of anarchist protest.
Officials from the host government have said they needed to hold the annual summit in a metropolitan area to ensure there were enough hotel rooms, and that they wanted to show off one of Germany's most international cities.
But critics claiming the government had miscalculated intensified their attacks Saturday. The conservative opposition leader in the Hamburg legislature, André Trepoll, slammed center-left Mayor Olaf Scholz for going easy on left-wing extremism. The Bild tabloid, Germany's top-selling paper, said both Mr. Scholz and German Chancellor Angela Merkel -- who is up for re-election in September -- bore responsibility for the events.
"The feeling of general security, which the state must guarantee, has ceased to exist in Hamburg in the last 48 hours," Julian Reichelt, a top Bild editor, wrote in Saturday's edition. "The horrific message of Hamburg is: if the mob wants to rule, it will rule."
After the summit ended Mr. Scholz and Ms. Merkel together met with several dozen police officers and thanked them for their work.
"Some people exercised unimaginable violence," Mr. Scholz said. "I thank those who say that it must nevertheless be possible for such summit meetings to take place in cities such as Hamburg and in a democratic country such as Germany."
Demonstrations against the summit continued more peacefully Saturday. More than 50,000 people marched in protest of what organizers described as "this cold and cruel world of global capitalism."
It wasn't immediately clear who the black-clad rioters were. They sometimes marched alongside peaceful demonstrators before attacking property or police. German Interior Minister Thomas de Maizière described them as "anarchists" from across Europe. "What we're seeing here is the opposite of democratic protest," he said. "These were wanton, extreme acts of violence out of lust for destruction and brutality."
Cord Wöhlke, co-head of Hamburg's Budnikowsky drugstore chain, arrived in the Schanzenviertel about 9 p.m. Friday to see one of his shops being looted. Rioters shattered the windows and tossed items into the street to be burned, he said.
The plunder lasted several hours, Mr. Wöhlke said, before the police moved in. Few of the rioters spoke German, he said, and Spanish-language graffiti saying "social war" was left behind. "We were all worried, but no one expected this level of violence," he said.
U.S. President Donald Trump, speaking Saturday at a G-20 event in the city to promote women entrepreneurs, mentioned the street protests. He praised Ms. Merkel and said the summit had largely proceeded "without much interruption," despite "quite a few people" who "seem to follow your G-20s around."
"You've been amazing and have done a fantastic job," Mr. Trump told the chancellor.
While world leaders were able to hold their talks on Hamburg's elaborately secured convention center sealed off from the commotion outside, the riots cast a shadow on the summit. On Friday, Mr. Trump's wife, Melania, was forced to skip an event with leaders' partners because protests made it unsafe for her to venture outside, her spokeswoman said.
On Saturday, French President Emmanuel Macron urged leaders to heed the protesters' concerns.
"We've been living in a town for two days that is attacked by hooligans to whom I will give no ground," Mr. Macron said. But, he added, Hamburg also showed "an expression of civil society that is beginning to doubt our ability to regulate globalization."
--Peter Nicholas contributed to this article.
Write to Anton Troianovski at email@example.com and Andrea Thomas at firstname.lastname@example.org
(END) Dow Jones Newswires
July 09, 2017 15:33 ET (19:33 GMT)