Riots broke out in Basel over the weekend as climate campaigners clashed with police.
Around 400 marched on Saturday, but were stopped from entering the centre of town.
Police say the demonstrators had come prepared for violence and their officers were targeted.
They say three officers were injured by fireworks and there was some property damage.
Military court sentences army recruit following on-duty sexual assault
Swiss motorcyclist requires multiple surgeries after Motorcycle Grand Prix crash
Swiss Indoors Basel ends with youngest ATP Top 100 champion
Switzerland is forgetting how to ride a bike
Man rescued from construction crane in Schaffhausen
Trees down, power out across western Switzerland
