Protesters torched cars and blocked roads Friday as German authorities called in reinforcements to try to control running street battles while leaders of the world’s biggest economies met for talks.

Rallying against global capitalism, protesters played a game of cat-and-mouse with riot police, trying to shut down major streets and disrupt the first day of the Group of 20 summit. 

By midnight, Schanzenviertel, a center of the city’s left-wing activism, had become a battlefield, where about 1,500 militant protesters had set up barricades, smashed store windows and lit fires in the streets. Special forces carrying firearms were trying to clear the area, as authorities shut down some of the surrounding train stations. Police said heavily disguised protesters were attacking officers and throwing Molotov cocktails.

Across Hamburg, smoke billowed from cars set ablaze. Armored police vehicles fanned out across the city and helicopters patrolled. At least 196 officers — and many protesters — were reported injured since clashes began late Thursday, and about 100 protesters had been arrested, police said Friday evening.

Cars burn during anti-G20 protests in Hamburg on July 7, 2017. (Social Media/Reuters)

Both numbers were expected to rise, as tussles continued late into the evening. Protesters persisted in their attempt to seize intersections and other public spaces after beginning the day by trying to penetrate a broad police cordon clearing traffic along routes linking the summit venue to the airport and hotels. 

“The G-20 says it stands for 80 percent of the world, or the world economy,” said Jana Schneider, 26, a criminology student in Hamburg. “Well, not me.”

One street blockade caused first lady Melania Trump to miss an event with the spouses of other world leaders. President Trump was the target of many protests.

Hamburg police called in reinforcements from across the country to join 20,000 officers already deployed. Forty-five water cannons were available to disperse crowds, and a no-fly zone was in place over portions of the city.

Crowds were expected to receive a high-profile boost after New York Mayor Bill de Blasio said he would join a major rally planned for Saturday.

The discord has produced an anguished debate, unfolding on the sidelines of the summit, about security and free expression, in a port city that, for a thousand years, has connected northern Europe to the far reaches of the globe. Its trademark openness is being tested as protesters — who could number as many as 100,000 by Saturday — turned the old merchant city into a site of a global contest over capitalism and environmental degradation, among many concerns.

Past summits have drawn similar demonstrations. But this year’s protest has targeted a triad of divisive figures: Russia’s Vladimir Putin, Turkey’s Recep Tayyip Erdogan and Trump.

They are among the foreign leaders being hosted by German Chancellor Angela Merkel at a downtown conference center and the lofty Elbphilharmonie concert hall, a crown jewel of the city, which is among the country’s most affluent and yet burdened by an unemployment rate higher than the national average.

“This week is about Angela Merkel’s austerity policy going global via G-20,” said Jan van Aken, a member of the German Parliament from the far-left Die Linke party.

He accused the German government of seeking to suppress protest, saying its approach was autocratic and would “make Erdogan, Putin and Trump feel at home here.”

The government is sensitive to this point. Merkel appealed for calm, saying on Friday that she respected “peaceful demonstrations” but considered violence “unacceptable.”

“The main issue is that the summit is again, after Brisbane, in a democracy,” said Wolfgang Schmidt, a Hamburg politician involved in summit planning. Summits in Turkey and China followed the 2014 meeting in Australia. “You want to make sure that protest and dissenting views are heard, but you also need to maintain security, and with 42 highly protected heads of state and finance and foreign ministers, it’s a challenge.”

Tensions boiled over Thursday near Hamburg’s harbor, as police tried to isolate a group of “black bloc” activists — known for their anarchist sympathies and for concealing their faces — from more than 10,000 protesters gathered for a “Welcome to Hell” demonstration.

“The police behaved very badly last night,” said Christian Buettner, 33, as he sat with other protesters blocking access to a bridge.

Some of the protesters played cards and drank iced tea. Elke Steven, who was monitoring the police response for a legal watchdog group, said police continued on Friday to turn too quickly to force. An officer deployed from Cologne said she sympathized with some of the activists’ complaints — but not their unwillingness to obey warnings to clear the streets.

Meanwhile, authorities defended their policing tactics. Hamburg’s interior senator, Andy Grote, told reporters that the amount of “criminal energy and the potential for violence” among protesters had been “shocking.”

But the approach of many protesters made for a stark contrast with scenes of looting and rioting in pockets of the city. 

Rather than being dragged from an intersection that police were trying to clear, Mona Jostem, 26, chose to leave of her own accord. “I’m not protesting the police,” she said. “But if we can delay the meetings or disrupt them in some way, maybe we can make them feel how fed up we are.”

Michael Steiger, 52, said he sympathized with the officers. But he said they would be wise to remember Germany’s history of political dissent — on issues as diverse as nuclear power and reunification — and the dangers of the state’s use of force against its own citizens.

“I understand they have to do it,” said Steiger, who works with the Boy Scouts in Greifswald, in northeastern Germany, in an effort to engage young people in the struggle against racism. He was born in Hamburg but moved east several years after reunification to join in advocacy work.

“For years now, Germany has proudly allowed protest, after great repression,” he said. “Why stop now that the world is watching?”