A Russian hacking group began attacking U.S.-based policy think tanks within hours of Donald Trump's presidential election victory, according to cyberexperts who suspect Moscow is seeking information on the incoming administration.

Three cybersecurity firms told Reuters that are tracking a spear-phishing campaign by a Russian-government linked group known as Cozy Bear, which is widely suspected of hacking the Democratic Party ahead of the election.

"Probably now they are trying to rush to gain access to certain targets where they can get a better understanding on what is going on in Washington after the election and during the transition period," said Jaime Blasco, chief scientist with the cybersecurity firm AlienVault.