Paul Whelan, the U.S. citizen recently arrested in Moscow on espionage charges, was caught “red-handed,” according to the news agency Rosbalt. A source in Russia’s law enforcement reportedly says Whelan spent years using social media to recruit Russians with access to classified data. Whelan’s lawyer, meanwhile, told the news agency that he expects his client to be released on his own recognizance, when the case comes before a judge.

Rosbalt’s source says Federal Security Service officers arrested Whelan at his room in the Metropol Hotel, five minutes after he supposedly accepted a flash drive with a list of all the employees working at a classified security agency. The source claims that Whelan used “highly non-standard methods for intelligence gathering,” registering accounts on social networks popular among Russians. He supposedly started this as far back as a decade ago, broadcasting his interest in Russia and the Russian language. Rosbalt’s source says Whelan sought out Russian Internet users “tracked and selected in advance by American intelligence as individuals who might have access to classified information.”

After two years of friending Russian Internet users, Whelan reportedly started visiting Moscow. “What stood out,” Rosbalt says, “was that Whelan wasn’t at all interested in pretty Russian girls, and preferred to spend his time drinking with male friends from the Internet.” Whelan was supposedly embedding himself in the private lives of potential information sources, going so far as to attend these people’s family celebrations.

Rosbalt’s source also speculates that reports about Whelan being dishonorably discharged from the U.S. Marines in 2008 for larceny could be part of a “cover story” invented to make it easier for him to operate in Russia.

On January 2, U.S. Ambassador to Russia Jon Huntsman visited Whelan at the Lefortovo Detention Facility in Moscow. Huntsman reportedly offered the American Embassy’s assistance, and later spoke with Whelan’s family by phone. U.S. Secretary of State Mike Pompeo says Washington expects to learn more about the charges and will demand Whelan’s return, “if the detention is not appropriate.”