Story highlights Clinton spoke at the 'Women in the World' summit in New York City

"A foreign power meddled with our election"

New York (CNN) Hillary Clinton referred to Russia's meddling in the 2016 US presidential election as an "act of aggression" on Thursday, in her most extended comments yet about a controversy that has consumed the earliest days of Donald Trump's presidency.

"I am deeply concerned about what went on with Russia," Clinton said at the "Women in the World" summit in New York City. "A foreign power meddled with our election and did so in a way that we are learning more about every single day."

The Russian hackings, she said, appeared to be a "more effective theft even than Watergate."

Accusing Russian President Vladimir Putin of wanting to "sow distrust and confusion, as well as influence, our election," the former secretary of state also said she supports an independent investigation into whether there was collusion between Russia and the Trump campaign.

Russians "will be back time and time again" if the United States doesn't take bipartisan "action together to hold whoever was involved accountable," Clinton warned.

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