The U.S. Embassy in Russia has told Russia to "stop playing games" in regard to the situation surrounding detained former U.S. Marine Paul Whelan, urging Russian officials to provide proof of his alleged espionage.
Embassy spokeswoman Andrea Kalan asked on social media on April 30 "why haven't Russian officials provided proof?" of Whelan's alleged spying and added that there was a "complete lack of evidence" in his case.
Kalan's comments came after Whelan was visited in Moscow's Lefortovo prison by U.S. Ambassador Jon Huntsman.
Whelan, 49, was detained at a Moscow hotel on December 28 and accused of espionage, a charge he denies.
Whelan -- who holds U.S., British, Canadian, and Irish passports -- could receive up to a 20-year sentence if he is found guilty.
Kalan added that Huntsman's visit was a "joke" because the prison's rules prevented the ambassador from reading letters to him from his family that he had not been allowed to receive and that he was banned from "talking about anything that actually matters."
"Complete lack of evidence + Paul's isolation = greater likelihood officials will try to get a forced false 'confession,'" Kalan wrote.
Russia's Federal Security Service (FSB) arrested Whelan, who was in Moscow for a friend's wedding, after a friend handed him a flash drive that allegedly contained classified information. Whelan said the drive was supposed to contain holiday photos.
His lawyer said Whelan believed it was a set up.
Whelan is due to be held in pretrial detention until May 28 while his case is investigated.