Microsoft has confirmed that the twelfth Russian spy detained by the US government was working with the organisation as a software tester, Businessweek reports.
A company spokesperson said that Alexey Karetnikov worked in the software development testing department at Microsoft, but had not managed to compromise sensitive company data.
According to the Washington Post, Karetnikov had entered the country some time in October and has been living in Seattle.
He was deported to Russia on Tuesday after admitting to immigration officials that he had been living illegally in the US.
Government officials have said that there was insufficient evidence to prosecute him as a Russian spy, but that security services had been monitoring Karetnikov from the moment he entered the country. They said that he had not obtained any sensitive information.
According to the officials, Karetnikov had no connection to the other ten individuals accused of spying for the Russian government, who were recently handed over to Russia in exchange for four US citizens accused of spying.