A nuclear reactor at the Olkiluoto nuclear power plant 220 kilometers northwest of Helsinki was shut down on Thursday after a big abnormal event which has caused severe radiations inside the unit. According to the Finnish Radiation and Nuclear Safety Authority, there is no radioactive release in the environment. The event was probably caused by a fault in the purification system for the reactor water. The Finnish authority has stated that “There is no danger outside the unit and no radioactive release is expected. Iodine tablets shall not be taken, and it is no need for other actions as staying inside. The radiation situation outside the unit is normal.”