Tapio Iinatti, deputy director of the prison, did not disclose any other detail about the incident, which was said to have taken place around 9am.
Once before in 2011, Pekka Luukkonen, the prisoner on the run, escaped the prison. He managed to stay at large for a couple of weeks on that occasion.
In 2012, he escaped the Sukeva prison and remained unaccounted for a week.
Iinatti said it seemed that Luukonen had become adept at finding escape routes. Pekka Luukkonen was not serving his sentence at Oulu prison; rather he went there on a personal visit.
According to the Criminal Sanctions Agency, three prisoners were on the run at the beginning of April. Last year, a total of 15 inmates went rouge.
