Geneva - Police in Switzerland on Wednesday detained about 20 foreign motorcyclists after they were caught riding at speeds of more than 200 kilometres an hour in what appeared to be a trans-European "cannonball" bike run.
Two of the bikers forced their way through a police roadblock in southwestern Switzerland but were later caught on the Simplon mountain pass, which heads into Italy, the Valais regional police force said.
The others were stopped in two different locations in the region, and their motorcycles were impounded, police spokesperson Jean-Marie Bornet told AFP.
"They wanted to get to Slovenia today. Well, they won't reach Slovenia today," Bornet said. "We have zero tolerance for this. There's no way that we'll tolerate this kind of stupid behaviour."
The group, from Britain, Denmark and New Zealand, will be questioned by an investigating magistrate before being released later on Wednesday, he added.
Bornet said the motorcyclists were spotted by other motorists weaving along a motorway at very high speed after leaving the Swiss city of Lausanne earlier in the morning. They were also seen speeding through villages.
"There was a concrete danger, this is not something abstract," he added.
Police were also examining equipment including video cameras on some of the motorcycles and were expecting to press charges of serious road offences including dangerous driving.
Some of the motorcycles carried numbers and stickers indicating they were part of a "cannonball bike run", Bornet said.
A website said to give details of the run dubbed "the third crusade" from August 21 to 27 gave no indication of the route.
It promised an average of nine hours a day of "intense riding" for national teams on the "very best mountain and backroad routes".