Police in Stuttgart have arrested 24 suspects over rioting and looting that erupted in the German city early Sunday morning.

Of those in custody, 12 are German citizens and at least seven of them are under the age of 18, said Vice President Thomas Berger. 

Speaking at a press conference, he told reporters the violence escalated at around midnight after officers began carrying out drug checks in Schlossplatz, the city's main square.

Police said hundreds of mainly young people who had gathered there started throwing stones and bottles at authorities, smashing patrol cars and breaking shop windows. They then tore through the main shopping district. 

Officers estimated that up to 500 people were involved in the unrest, which took several hours to bring under control.

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'Unprecedented' violence

Police President Frank Lutz said the level of violence against officers was "unprecedented," adding that the city's police presence would be beefed up in the coming weeks to prevent the scenes from being repeated.  

"These are incredible events that have left me stunned, and that I've never experienced in all my 46 years of police service," he said.

He said police had ruled out any political motive for the violence, pointing instead to partying youths. 

"We can rule out left-wing political or any political motivation for these acts of violence," Lutz added.

Police also confirmed that at least seven people would appear in court on Monday.

Almost 300 police were deployed to the city, including around 100 reinforcements called in from other precincts. Some 19 officers were injured in the violence, Berger said. Forty shops were damaged and nine were looted.

DW reporter Rebecca Staudenmaier tweeted from the Königstraße shopping district on Sunday, describing how passersby were stopping to take photos of storefronts that were damaged in the riot.

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Investigation underway

Stuttgart police have set up a 40-person team to investigate the rioting, and they're appealing for any witnesses who may have footage or images from Sunday morning to come forward. 

"I want to be clear: What happened last night is not acceptable, a line was crossed," Stuttgart Mayor Fritz Kuhn said. "Stuttgart has never experienced this kind of attack on the police … this cannot happen again." 

Winfried Kretschmann, the premier of the state of Baden-Württemberg where Stuttgart is located, condemned "this brutal outbreak of violence."

"These acts against people and things are criminal actions that must be forcefully prosecuted and condemned," he added.

Sascha Binder, a regional politician from the center-left SDP, described the violence as "civil war-like scenes."

nm/mm (AFP, dpa, Reuters)