The identities or nationalities of the victims have not been revealed, but police say victims included one female and two males. Early Wednesday Police Inspector Ari-Pekka Lehtinen said that officials still had not determined the cause of the blaze.
Later Wednesday morning officials reported that one of the bodies they found, a male, had likely been dead long before the fire started on Tuesday. All of the bodies found were middle aged, according to police.
Rescue services were alerted to a fire on Honkaistentie, located on the island of Hirvensalo in Turku, at about 10:30 Tuesday evening.
When rescue units arrived flames could be seen through a top-floor window of the three storey building, and the blaze spread quickly to the roof, according to officials.
The entire top floor of the building was destroyed by the fire, which also left much of the building uninhabitable. There are a total of ten apartments in the building.
According to police the Safety Investigation Authority is scheduled to inspect the scene to determine the cause of the fire.
More information about the fire is expected later on Wednesday, police said.
Updated: Includes details about the victims gender, age and time of death.