The tourist bus carrying 40 passengers collided with two trucks near the Winterthur-Wulflingen exit on a motorway not far from the northern city of Zurich, Swiss police said."Fifteen people were injured, one of them seriously," Zurich's cantonal police said in a statement adding that the cause of the accident remained unclear.According to the ATS news agency, the bus was carrying tourists from Sri Lanka.

The driver of the bus and a female travel companion riding up front were stuck and needed to be extracted by rescue workers, police said.The driver suffered moderate injuries, while the woman was seriously injured, they said.Twelve of the tourists were meanwhile slightly injured, as was the driver of one of the trucks, police said.