Three Swedes have been charged with industrial espionage after allegedly leaking information from telecoms equipment giant Ericsson.
The company said in a statement that the three people were either employees or former employees, although it would not say what information had been handed over.
They have allegedly been passing secret documents to a foreign intelligence service for some time.
Police said that the arrest of the main suspect took place as he was meeting a foreign intelligence officer. The other two are charged with helping the ringleader obtain the information.
An Ericsson spokesman said that the damage was limited as the delivery of the information was discovered and stopped.
However, the police said that it is impossible to estimate what repercussions the handing over of secret documents to a foreign power might have for Swedish security.
The investigation is at a sensitive phase, and police could not give any further information at this stage, including the name of the other country involved.
As well as making telecoms equipment, Ericsson is involved in defence work for the Swedish government. Its Microwave unit is developing missile and radar systems for planes such as the JAS 39 Gripen fighter jet.
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