Spy Hard: US Officials Explain Why It’s Hard to Track Russian Agents

US officials complain that the methods and technologies employed by alleged Russian intelligence agents operating in the United States make it difficult for local authorities to keep track of their activities.

According to current and former US officials cited by Reuters, it’s easy to access commercial encryption technology and the increased presence of Russian agents in the US has made it hard for the FBI to keep up with them.

"It’s more complex now. The complexity comes in the techniques that can be used," one of the officials said.

The news agency's sources also claimed that Russian intelligence operatives "have wormed and hacked their way into American companies, schools, and even the government," actively recruiting both Americans and Russian immigrants, infiltrating computer networks and setting up front companies.

Earlier the United States and a number of other countries expelled more than 150 Russian diplomats in response to the alleged nerve agent attack against Skripal and his daughter Yulia in Salisbury, England. London described the move as the "biggest expulsion of Russian spies since the Cold War."

READ MORE: Russian Foreign Intel Service Officers Among Expelled Diplomatic Staff — Chief

Former FBI espionage chief Michael Rochford warned, however, that the mass expulsion of "spies" posing as diplomats might pose a problem for US security services as it won’t be immediately clear who might be a spy among the replacements Moscow will send.