French officials have opened an investigation into the attempted murder of a police officer and Germany’s interior minister has called for harsh penalties after peaceful and mainly youth-led protests across Europe ended in violence.In Portugal, police – some with dogs – cleared protest camps with baton charges, while security forces in Switzerland were attacked with paving stones.Protests over the education system, deteriorating public services, declining prospects, unaffordable housing and the spiralling cost of living have shaken a number of countries this autumn.Violence erupted in the French capital as well as Marseille, Grenoble, Bordeaux, Lyon and Toulouse on Saturday night after an estimated 320,000 demonstrators, some in Halloween costume, took to the streets.Protesters in Halloween costumes gather in the La Plaine square in Marseille. Officials say 320,000 people took part in protests across France.

Photograph: Sener Yilmaz Aslan/Getty ImagesAs the rallies ended, masked and hooded rioters arrived and caused what the interior minister, Laurent Nuñez, described as an “extraordinary” level of violence. More than 770 people were arrested.In Paris, the prosecutor’s office said incendiary devices were thrown at a group of about 15 gendarmes and police officers and a formal investigation had been opened for “attempted murder of persons vested with public authority”.Injuries reportedly included second-degree burns in an incident captured on mobile phone video and shared on social media and broadcast on French television.A protester in a Batman costume salutes in front of a fire started by rioters in Frankfurt.

German authorities have promised a strong response. Photograph: Kai Pfaffenbach/ReutersThe level of physical violence and looting was significantly lower than on 17 October, when 2,600 people were arrested and as many as 3,000 shops pillaged in one of the worst nights of urban unrest in France’s recent history.In Germany, looters and rioters ⁠rampaged through Frankfurt, the country’s financial hub, damaging stores and injuring more than 100 police officers.“The rioters and looters will be identified and held accountable,” said Alexander Dobrindt, the hardline interior minister.

He singled out “violent left-wing groups and troublemakers from the migrant community”, adding: “Tough penalties must follow this breach of the peace.”Riot police clear Lisbon’s Rossio Square of activists protesting over housing affordability. Photograph: Manuel de Almeida/EPADobrindt told the tabloid newspaper Bild that deploying a heavy police presence across multiple locations had been effective. “Excesses of ​violence like those ‌in Paris were ​prevented thanks to our ​highly committed police forces,” he said.More than 100,000 protesters marched in over 30 German cities on Saturday to demand better ⁠education and lower living costs in protests led by the “Gen Z regelt” (Gen Z will sort it) campaign.Hooded rioters ⁠damaged 17 Frankfurt shops, looting five of them, and threw missiles including petrol bombs, according to Roman Poseck, the state interior minister for Hesse.More than 100 of the 1,300 police officers deployed in the city were injured and 54 suspects, ‌aged from 13 to 29, were arrested. “I am shocked by what I have seen, and there is no point in sugar-coating it.

Let me make this very clear: things cannot go on like this,” Poseck said.skip past newsletter promotionafter newsletter promotionAn anti-government protest in Tirana turned violent with protesters hurling stones and petrol bombs at police. Photograph: Vlasov Sulaj/NurPhoto/ShutterstockMost of those arrested were German nationals, the minister said, adding that police estimated they had been confronted with “between 1,000 and 1,500 violent troublemakers, predominantly from a migrant background”.Violence also broke out Saturday night in Cologne, where police used water cannon to disperse the crowd, and in Berlin, where protesters attacked police with bottles and fireworks.

Gen Z regelt posted a statement distancing itself from all violence.In Portugal, riot police removed protesters by force from Rossio Square in Lisbon at about 4.30am on Sunday after thousands of people angry at the housing crisis marched through the city on Saturday and set up camp.Protesters in Halloween costumes at an unauthorised demonstration in Marseille over the high cost of living. Photograph: Coust Laurent/ABACA/ShutterstockThe protesters want Portugal’s minority centre-right government to withdraw a ⁠bill that makes ⁠evictions easier and ends rent caps on new leases.

A smaller camp in Porto was also cleared by force.In Albania, masked protesters hurled stones and firebombs at police in the capital, Tirana, on the margins of a demonstration demanding the resignation of the prime minister, Edi Rama, over perceived corruption.Youths threw paving stones and firebombs at police and set fire to rubbish bins at the end of a largely peaceful protest. The interior ministry said on Friday that 350 people had been hurt in the protests, including 200 police, with 269 minors arrested.Riot police in action in Paris.

Almost 800 people were arrested across France for public order offences. Photograph: Bernard Jules/ABACA/ShutterstockIn Switzerland, hundreds of protesters gathered in Zürich and Basel on Saturday night for unauthorised demonstrations – both of which ended in violence – under the slogan: “We’ve had enough in Switzerland, too.”In Zürich, police used water cannon, teargas and rubber bullets to disperse rioters attacking them with fireworks, bottles and stones, Swiss media reported.

A police patrol car was damaged and rubbish bins and electric bikes set on fire.In Basel, police said about 150 people gathered in the city centre at around 9pm. Shop windows were smashed, facades tagged with graffiti and bins and bikes set on fire, with incidents also reported in Geneva.