President Trump continued his assault on the probes into Russia’s involvement in the election by blasting Hillary Clinton for colluding with Democrats to beat Bernie Sanders.

“Hillary Clinton colluded with the Democratic Party in order to beat Crazy Bernie Sanders. Is she allowed to so collude? Unfair to Bernie!,” Trump wrote Sunday morning.

Hacked emails from the Democratic National Committee and released on WikiLeaks last summer show officials in the organization criticized the Vermont senator, who challenged Clinton in the primary race, even though publicly they appeared to remain neutral.

Trump has been lashing out on Twitter about the election since the Washington Post reported on Friday that former President Obama was alerted to Russia’s meddling last summer but was conflicted about how to handle it so he wouldn’t appear to be tilting the election toward Clinton.

“Just out: The Obama Administration knew far in advance of November 8th about election meddling by Russia. Did nothing about it. WHY?,” Trump tweeted on Friday.

A number of congressional panels, including the FBI and special counsel Robert Mueller, are investigating Russian involvement in the election and any links to the Trump campaign.