Hillary Clinton said definitively on Sunday that Russian intelligence was behind the recent hacking of the Democratic National Committee, which resulted in the leak of thousands of internal emails and voicemails that party officials had exchanged.

“We know that Russian intelligence services hacked into the DNC, and we know that they arranged for a lot of those emails to be released, and we know that Donald Trump has shown a very troubling willingness to back up [Russian Prime Minister Vladimir] Putin, to support Putin,” the Democratic presidential nominee said in an interview with Fox News’ Chris Wallace.