The office of the U.S. Director of National Intelligence on Tuesday said Russia was "likely" behind a string of hacks identified last month that gained access to several federal agencies.

The office, along with the FBI, the National Security Agency, and Cybersecurity and Infrastructure Security Agency inside the Department of Homeland Security, in a joint statement, said the hackers' goal appeared to be collecting intelligence, rather than any destructive acts. They said they had so far identified "fewer than 10" agencies that were hacked.

The agencies said that the actor, "likely Russian in origin, was responsible for most or all of the recently discovered, ongoing cyber compromises of both government and non-governmental networks." The investigation is continuing, they said, and could turn up additional government victims.