Jan 25, 2010, 10:56 GMT
Madrid - The trial began in Spain on Monday of a suspected double agent charged with endangering national security by selling confidential information to Russia.
Roberto Florez, a former agent of the National Intelligence Centre (CNI), faces up to 12 years in prison if found guilty of treason.
If he is only found guilty of revealing secrets, he could be handed a sentence of up to four years.
Florez' lawyer Manuel Olle denied the charges against his client, pledging to seek his acquittal on entering the courthouse in Madrid.
Florez worked with the CNI from 1991 to 2004.
He was detained in 2007 on the Canary Island of Tenerife, where police found evidence suggesting spying in his home.
The evidence included confidential CNI documents, DVDs, CDs, cassettes, computer discs, as well as two letters sent by Florez to the then second-in-charge of the Russian embassy in Madrid.
In the letters, the Spaniard offered to disclose to Russia information on the identities of Spanish secret agents abroad and on the structure of the CNI.
Florez was believed to have offered to sell the information for 200,000 dollars (150,000 euros).
The alleged spying would have occurred at a time when Spain was a staunch ally of the United States in the Iraq conflict and could have been thought to possess information which was of interest for foreign intelligence services.
Olle admitted that the letters written by Florez 'are there,' but promised to explain their existence in court.
Florez' defence was expected to argue that there was no evidence of any classified information ever arriving in Russian hands.
The trial was taking place behind closed doors for concern that classified information would be revealed in court.
The Russian to whom Florez' letters were addressed to was not expected to be among the witnesses. Press reports said Spain wanted to avoid creating strain in its relations with Russia.
When Florez was arrested in 2007, the Russian embassy denied having had contacts with him.
The trial is unusual in Spain, where nobody has been found guilty of treason since the country became a democracy after the death of dictator Francisco Franco in 1975.
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