Sipachev had admitted working for the Pentagon, the court said

A Moscow court has sentenced a Russian national to four years in prison for handing over state secrets to the US.

Gennady Sipachev was found guilty of sending classified Russian military maps to the Pentagon via the internet.

The maps can be used to make the targeting of US cruise missiles against Russian targets more accurate, Russia's security service officials said.

The court said that Sipachev had made a guilty plea bargain with prosecutors in exchange for a lighter sentence.

"Sipachev co-operated actively in the detection and investigation and also pointed to criminal activity by other individuals which helped prevent further damage to the security of Russia," said the court's ruling.

US silent

Sipachev was found guilty under Article 275 of Russia's criminal code - "state treason in the form of espionage". The charge normally carries a sentence of up to 20 years in prison.

The court said that Sipachev - whose age and occupation have not been disclosed - would be serving his sentence in a high-security prison.

Russia's security services (FSB) said Sipachev had first raised their suspicions in 2008.

The FSB said it later found that he had been sending top secret Russian military maps to a Pentagon's in-house intelligence service, which acted under the cover of a different organisation.

There has been no comment from the US on the issue.