Story highlights Russians "continue to do all kinds of stuff" against American political organizations, a US official said

A Clinton campaign official said they received notice "a state actor" was trying to hack private accounts

(CNN) Russian cyberhacking activity has continued largely unabated since the November election, including against US political organizations, US officials briefed on the investigation told CNN on Thursday.

Among the attempted cyber breaches are phishing attempts targeting Democratic presidential nominee Hillary Clinton's campaign, one official says. The attempt to breach the Clinton campaign was unsuccessful, investigators tell CNN.

The attempts appear to trace back to some of the same Russian hackers behind the breaches of Democratic Party organizations in the past year, one official said. The FBI has expanded its ongoing probe of Russian hacks to include the more recent attempts.

Russians "continue to do all kinds of stuff" against American political organizations, think tanks and thought leaders another US official said.

"It's not like the one and done deal here. They continue to engage in this operation around the clock." This person said the US is constantly trying to shut down access to different avenues for cyber attacks. "There's a lot that gets done with our own security services," the official said. In terms of retaliation against Russia this person said a variety of options are on the table but everything is being carefully considered because "right now it's like the old cold cyber war and the last thing you want to do is turn it into a hot shooting war."

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