More than 200 public transport routes operated by Helsinki Regional Transport (HSL) were cancelled on Friday morning due to a shortage of drivers.
A downed power line in Espoo further contributed to some cancellations, according to the authority, while heavy snowfall has also caused some challenges for public transport in the capital area.
The ongoing problems have mainly affected bus schedules.
"The route changes seem to be spread fairly evenly over various areas, so the problem is not concentrated in a specific area," HSL's communications department told Yle.
Sick leaves and other types of absences are to blame for the staff shortage, according to VR Group subsidiary Pohjolan Liikenne.
"Pohjolan Liikenne is the third largest transport operator for HSL. One driver can carry out several dozen trips during their shift, so even one absence that cannot be covered creates a big shortage," HSL's communications officer Joona Packalén said.
Packalén added that the situation is unlikely to improve within the next 24 hours, adding that travellers should prepare for more cancellations throughout Friday.
Commuters can keep up to date with the changes via HSL's social media (siirryt toiseen palveluun) channels and their app. The route guide (siirryt toiseen palveluun) is constantly updated to include new times and alternative route options, according to the transport authority.
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