Violence broke out in several Swiss cities late on Saturday, after anti-globalisation demonstrators held a generally peaceful protest in the Swiss resort of Davos near a meeting of the World Economic Forum. The worst clashes were in Zurich.
Protests were held in Zurich, Geneva and Bern, following the demonstration in Davos earlier in the day.
The worst violence was reported in Zurich where police used tear gas and rubber bullets against dozens of demonstrators who went on the rampage in the city.
Police said the protestors, arriving back from the Davos area by train, had set fire to cars and damaged buildings when they returned to Zurich.
They arrested around 100 people on Saturday evening.
About 200 people were involved in clashes with police in Bern. Police said they were pelted with bottles and stones, before the protestors fled into a youth centre. Two people were arrested.
And in Geneva, about 200 people held a rally, some of them spraying the walls of the World Trade Organisation. They did not manage to break in to the building.
The violence broke out after a largely peaceful rally by protestors in Davos, close to the congress centre where the World Economic Forum is taking place.
At one stage police used water cannon to drive back about 300 protestors. They had succeeded in getting past two police barricades, but were swiftly driven back by police.
No injuries or arrests were reported, and the demonstrators dispersed peacefully.
Police authorities in Davos said they were pleased with their efforts to thwart violent protests.
"We managed to ensure that the conference went ahead smoothly," said Markus Reinhard, the police chief for Canton Graubünden. "We prevented the unauthorised protests without causing any injuries or damage."
Around 800 people were prevented from travelling to Davos after police took them off trains at Landquart, the main transit point for getting to the resort.
A stand-off led to clashes in Landquart, and police used tear gas against the demonstrators.
The authorities had effectively sealed off Davos with a series of roadblocks. Rail services to Davos were suspended, and the border crossing point at Chiasso in neighbouring canton Ticino was closed for a time to prevent demonstrators from reaching the resort.
Groups opposed to globalisation had indicated they would be out in force, despite a ban on their demonstration by the local authorities.
Last year's World Economic Forum summit was marked by violence, with police using tear gas and rubber bullets to disperse crowds of protesters. To prevent a repeat-performance this year, a record number of 1,000 police were deployed in and around Davos.
Clashes between police and protestors have been a regular occurrence at economic summits in recent years; meetings of the World Trade Organisation, the World Bank and the International Monetary Fund have all been disrupted by demonstrations.
swissinfo with agencies