Helsinki police suspect improperly engaged handbrake caused Senate Square bus accident

A woman remains hospitalized with serious but non-life-threatening injuries after a driverless tourist bus rolled downhill in central Helsinki on Saturday, striking another parked bus on Unioninkatu street, according to Helsinki police.

Investigators have found no evidence of a technical fault in the vehicle, preliminary findings suggest. “It appears the handbrake was either not engaged at all or was engaged incorrectly,” Anssi Enqvist, the duty investigation leader for Helsinki police, told Yle on Sunday.

The Hop-on Hop-off sightseeing bus, operated by Stromma Suomi, traveled several dozen meters before colliding with a second parked bus. The company’s managing director, Peter Kåla, described such incidents as “extremely rare” in comments to Yle on Saturday. Enqvist confirmed he could not recall a similar case during his tenure.

Authorities are investigating the incident as a traffic safety violation and causing bodily harm, though charges may be adjusted as the probe continues. A final determination on the cause could take weeks, Enqvist noted.

The injured woman was trapped beneath the runaway bus during the incident, which occurred at the intersection of Senate Square and Unioninkatu.