HELSINKI (Reuters) - Finland’s nuclear safety authority said on Thursday that radiation levels had risen following an incident at the Olkiluoto 2 nuclear unit in western Finland but there was no radioactivity leakage outside and the situation was under control. “There are no indications of a fuel leak from the incident and there are no longer any exceptional radiation levels inside the plant,” the authority, STUK, said in a statement. It said it had been informed of elevated radiation levels at the reactor at around 1 p.m. (1100 GMT). “This is a significant and an exceptional incident and we consider it important to spread correct information about it,” Finland’s minister of social affairs and health Aino-Kaisa Pekonen told reporters. The elevated readings stemmed from a room regularly showing higher values during normal operations, and no power company employees had been exposed to radiation or were injured, it added. Jarmo Tanhua, CEO of the nuclear power plant operator TVO, said the incident was an unparalleled event in the facility’s history. TVO is a consortium of power and industrial companies. The International Atomic Energy Agency said STUK had informed it of the incident and that it would provide public information as it became available. Olkiluoto 2, which has a capacity of 890 megawatts, shut down and would remain offline until Saturday, according to information posted by TVO via power exchange Nord Pool. “They have to check that everything is OK and then they have to have our permit from STUK to start the reactor again,” Tomi Routamo, deputy director of STUK, told Reuters. TVO was investigating the cause of the radiation spike, which may have originated from contaminated filter material reaching the coolant system, he added. Intraday power prices in Finland spiked as high as 2,000 euros ($2,426) per megawatt hour following the incident, Nord Pool data showed. ($1 = 0.8245 euros)