Two Lithuanian men convicted of spying in Russia and a Norwegian citizen serving a 14-year sentence have been freed as part of a spy swap, authorities said.

Yevgeny Mataitis and Aristidas Tamosaitis, who were convicted in 2016, have been reunited with their families, according to Lithuanian spy chief Darius Jauniskis.

In Oslo, Norwegian Prime Minister Erna Solberg said Frode Berg was handed over to Norwegian authorities in Lithuania.

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“We are happy that Frode Berg is now coming home to Norway as a free man,” Ms Solberg said. “I would like to thank the Lithuanian authorities for their cooperation and for their efforts to free Berg.”

There was no immediate word on what has happened to Nikolai Filipchenko and Sergey Moiseyenko, two Russians who were pardoned earlier in the day by Lithuanian President Gitanas Nauseda.

Norway’s foreign minister said the time in prison has “been a huge burden for Frode Berg and his family”.

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Ine Eriksen Soereide said Norway had “worked systematically” to get Mr Berg, a retired border inspector, freed after his arrest in Moscow in December 2017 on espionage charges for collecting information about Russian nuclear submarines.

Prosecutors asserted that he was caught with documents he had received from an employee of a military facility who was shadowed by Russian intelligence.

Mr Berg’s Norwegian lawyer, Brynjulf Risnes, said on Twitter that his client had crossed into Lithuania from the Russian exclave of Kaliningrad.