In the city of Lahti, one person died and another was seriously injured in a collision involving a truck, a motorcycle and two cars. Several other people were injured.
In Jyväskylä, a cyclist died in a collision with a bus in the center of the city.
Earlier in the day, one person died in a crash at a railway level crossing in the south-eastern town of Loviisa. Eyewitnesses said a car driven by a pensioner collided with a goods train.
Eight people have died so far this year in accidents at level crossings.