Nationwide youth-led protests in Germany were marred by rioting, looting and attacks on police Saturday as largely peaceful daytime demonstrations gave way to serious unrest in Frankfurt and Cologne that evening.

Rioters smashed shop windows, looted stores, and threw Molotov cocktails at police in central Frankfurt. In Cologne, attackers threw bottles and bicycles at officers near the city's famous cathedral.

Politicians and police blamed the violence on groups of masked, radical left-wing activists.

Unrest followed demonstrations by tens of thousands of young Germans demanding better schools, relief from rising living costs, and greater social justice. Protesters also vented anger at conservative Chancellor Friedrich Merz. Many protests were peaceful.

Participants carried placards with slogans including "Our future is not for sale," "System change, not climate change," "Education, not bombs," and "Eat the rich."

The "Gen Z regelt" (Gen Z Takes Charge) initiative had expected demonstrations in more than 30 German cities, drawing inspiration from weeks of large-scale youth demonstrations in France and elsewhere in Europe. Despite strong interest on social media and widespread media coverage, turnout was more modest than anticipated.

Before the evening's chaos, organizers hailed the protests as a success, reporting more than 100,000 participants nationwide in major cities and smaller centers like Erfurt, Münster, Nuremberg and Karlsruhe.

Nationwide police figures were unavailable, though individual cities released their own turnout tallies.

Frankfurt experienced some of the worst scenes. Rioters smashed shop windows and broke into stores to steal trainers and other goods, dpa journalists observed.

Rioters attacked a specialist firearms shop late Saturday. Police arrested several people and recovered two weapons from the store. Officials did not specify the type of weapons.

Rioting engulfs Frankfurt

Rioters also set trash bins on fire, tore down street signs and smashed shop windows with signs and other objects.

Police reported Molotov cocktails were thrown at officers as violent clashes continued downtown.

At about 10 p.m., officers sealed off a section of the Zeil, one of Germany's busiest shopping streets and urged people to avoid the area.

Authorities deployed special police units (SEK) as unrest continued late into the night. Authorities said more than 1,000 security personnel deployed downtown shortly before midnight. Police reported about 30 people taken into custody.

Earlier, up to 8,000 people joined a largely peaceful demonstration, police said, while organizers estimated turnout at about 9,000.

The protests began in the afternoon on the banks of the Main river near the European Central Bank. The procession moved through central Frankfurt for several kilometers over several hours. Organizers urged participants to remain peaceful.

However, the situation deteriorated hours later when police came under repeated attack with stones, bottles, and firecrackers.

Officers used water cannons and broke up the demonstration in the early evening, but violent groups remained active downtown after many peaceful protesters left.

Hesse state Interior Minister Roman Poseck said several police officers were injured, adding that one officer may have suffered more serious injuries.

Poseck said about 100 suspected left-wing extremists were responsible for the evening violence.

In Cologne, about 200 people, including some rioters, were involved in disturbances around the city's cathedral, next to the main railway station.

Attackers threw bottles and bicycles at police officers during the unrest. One person was injured.

Five people were detained, police said.

In a nearby side street, someone smashed a window with a thrown electric scooter.

'Gen Z regelt'

After repeated clashes, police dispersed the large crowd outside the cathedral to deescalate the situation. However, smaller groups continued moving downtown, with occasional fireworks set off.

A police spokeswoman said the later incidents appeared linked more to Halloween celebrations than to the earlier youth protests.

Disturbances were also reported in other cities.

In Berlin, police broke up an evening demonstration after officers were attacked with stones and protesters set off fireworks. Police said 27 officers suffered minor injuries and up to 56 demonstrators were temporarily detained.

About 700 people initially gathered at Rosenthaler Platz downtown for a march under the slogan "Gen Z Has Had Enough!" toward Prenzlauer Berg. The crowd grew to as many as 3,500 participants, police said.

Police said the atmosphere was tense from the outset, with many participants dressed in black and wearing masks. Groups on the political left organized the march, and pro-Palestinian activists also took part.

After police ended the demonstration early in coordination with organizers, smaller groups continued moving through nearby streets.

"It's now like a game of cat and mouse," police spokesperson Julia Scholz said. The situation calmed by about 8 p.m.

The evening march was separate from the main "Gen Z regelt" demonstration, where up to 5,000 people gathered peacefully at the Brandenburg Gate earlier in the day.

In Hamburg, a largely peaceful demonstration of about 6,700 people was followed by disturbances near the main railway station.

People dressed in black, some with covered faces, set off fireworks, tore down plastic construction barriers, and set them on fire. Police used water cannons to extinguish the flames and pepper spray to disperse the crowd.

In Bremen, where about 2,800 people demonstrated, isolated incidents included officers being punched and kicked, and at least one trash container set alight.