Finland said Thursday its foreign ministry had been the target of "massive" digital spying detected in the beginning of the year, but its most sensitive information was not affected.
Foreign Minister Erkki Tuomioja said police had launched a probe into the spying which he described as "very sophisticated."
The MTV3 television station which first broke the story reported that the Russian and Chinese secret services were suspected by Helsinki of being behind the digital attacks.
"It is very embarrassing," Tuomioja told journalists of the spying which authorities believe had been going on for a long time, however he said the most sensitive information, particularly relating to international relations, had not been uncovered.
Finland has informed other European Union nations of the breach in security.
Experts were not surprised that the spying had taken place.
"In Finland authorities have been too innocent. In France for example the use of Blackberry smartphones has been banned for a long time" among high-ranking officials, independent digital expert Petteri Jarvinen told AFP.
"The fact that Finland didn't detect the acts of espionage itself which have lasted for years is very embarrassing," he said, referring to the fact that clues to the spying had come from abroad.
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