UPDATE 1-Finland says it was spied on for years
(Adds details about the instances of spying, quotes)
HELSINKI, July 2 (Reuters) - Foreign governments conducted a cyber attack against the Finnish foreign ministry and were able to spy on it undetected for years, gaining access to sensitive materials, the ministry and the Finnish secret service said on Wednesday.
The ministry was the target of two separate instances of spying, the Finnish Security Intelligence Service said. It found out about the first case in early 2013, which it said had been going on for years. It did not know when the spying started.
The police were tipped off by another country. When investigating the first case, they detected a second, more serious security breach, it said.
The attacks were conducted by planting malicious software on ministry computer equipment.
Antti Pelttari, head of the Security Intelligence Service would not comment on which country was involved.
"We will not single anyone out, simply say that they were done by governmental actors. We will not name them," Pelttari told a news conference.
Pelttari would not comment on whether the attacks came from one country or two different ones. Several other Western countries, including Belgium, have been targeted with similar attacks, he added.
Those spying on the foreign ministry had access to lots of documents, the police said, but added the exact content of all compromised materials were not known yet.
"The information gleaned can have had an impact on negotiations, and can have caused damage to Finland's national interest," Peter Stenlund, secretary of state at the foreign ministry, said.
Due to the knowledge gained in the investigation, the ministry has been able to stop several other cyber attacks, Stenlund said.
With the investigation, the perpetrators also know they have been identified.
"They know that we know," Stenlund said.
(Reporting by Sakari Suoninen; editing by John Stonestreet and Louise Heavens)