Rail services between Oulu and Kemi were disrupted on Sunday morning after a fault was found on the line, according to infrastructure manager Fintraffic.
The Fintraffic track maintenance unit told STT that repair work had begun around 7:30 on Sunday morning and would take around an hour.
The track was eventually repaired after 11am, with services returning to normal over the course of Sunday.
VR said the Intercity train from Helsinki to Kemijärvi was around 5-6 hours late and the sleeper from Helsinki to Rovaniemi was two hours late.
Sunday's 19:15 sleeper train from Kemijärvi to Helsinki will be replaced by a bus service between Kemijärvi and Rovaniemi, leaving from outside the station.