The city of Helsinki reported major computer systems failures that started on Tuesday night and continued into Wednesday morning.
The disruptions were due to technical updates carried out by network services firm Elisa, according to the company's communications chief Maija-Liisa Kasurinen.
Elisa said on Wednesday they were working on getting the services back online.
Public transport affected
Most of the city's public transportation ticket machines were also out of action. Helsinki Regional Transport Authority's (HSL) tram and metro systems were affected by the network failure, resulting in delays to many services.
HSL's bus, metro, tram and train stop information screens were downed by the outage.
The computer failure also affected Helsinki's health care services. On Wednesday morning the city's health centre telephone system was down. City officials urged people requiring emergency services to call the public emergency telephone number 112.
City services phone lines facing problems
In addition, there were reports of city telephone numbers and email system outages, and problems were reported at some libraries across the city with some services out of service.
However, online services and web pages maintained by the city appeared to be functional, including HSL's websites.