Around 100 anti-globalisation protesters attempted to block an inter-city train from crossing the Swiss border into Italy on Monday night.
Demonstrators from Switzerland, Germany, Italy and the United States marched on to the railway tracks at Chiasso in canton Ticino on the border with Italy.
As the Dortmund-Milan express train was preparing to leave the station, the protesters tied themselves to the track.
The demonstrators said they were protesting against a decision by Italian border police to refuse entry to a small group planning to travel to Genoa, venue for the forthcoming G8 summit of leading industrialised nations.
The train was delayed for one hour, before Swiss police intervened to force the demonstrators off the track.
Eyewitnesses say police later fired tear gas into the air and used rubber bullets in a bid to disperse the crowd of protesters, but no injuries or arrests were reported.
The latest anti-globalisation protests come just four days before the G8 summit is scheduled to begin.
The Italian authorities, preparing for an influx of more than 100,000 anti-globalisation protesters ahead of the weekend summit meeting, have said they are ready to deploy at least 15,000 armed police and military personnel around Genoa.
Police presence at main border points around the country has also been stepped up in anticipation of further isolated clashes with protesters attempting to enter the country.
swissinfo with agencies