Three former employees of the Swedish telecomms equipment maker Ericsson have been imprisoned after being found guilty of industrial espionage.

An engineer who was laid off from Ericsson in August 2001 was sentenced to eight years in jail for handing secret company documents to Russian intelligence agents last year.

Two of his former colleagues, who gathered some of the information, were also convicted. One received a three-year prison sentence while the second was jailed for one year.

According to the court, the documents contained "technical information with connection to mobile telephony and fixed telephony as well as to both existing and future systems." All persons involved in the trial have been ordered not to discuss the documents for 20 years.