Police are continuing their investigation into the deaths of two Russian men in a rare accident on Sunday in the southeastern port of Kotka.
The men belonged to the crew of a cargo ship registered in Gibraltar.
Against regulations, the three men had entered the ship's cargo hold without an oxygen apparatus. The damp wood chips in the hold had depleted much of the oxygen.
Two of the men died of asphyxiation, while the third managed to get out. He is now in hospital care.
Experts suspect it was an occupational accident. Police in Kotka have launched an investigation and are questionning the ship's captain on Monday.