A bus operated by Dutch tour operator Oad, carrying 49 Dutch nationals, has been involved in a serious accident in the Graubünden region of Switzerland. Local police report multiple fatalities as a result of the incident. The crash may have been caused by an evasive maneuver to avoid falling rocks on the road. Authorities are currently investigating the circumstances surrounding the accident. Further details are emerging through a liveblog providing the latest updates. The incident has prompted a significant emergency response in Graubünden. The Dutch government has been notified and is providing assistance to those affected.