As special counsel Robert Mueller prepares to reveal more details about his investigation into Russian meddling in the 2016 election in the face of filing deadlines, President Trump is unleashing a barrage of tweets aimed at everyone from Mueller to former FBI director James Comey to former Justice Department officials, and says his team has a “counter report” that is already 87 pages long.

Trump began his tweet-storm Friday morning by criticizing Mueller’s investigation into Russian meddling in the 2016 election, and what he sees as conflicts of interest in the case.

Trump started with Mueller’s relationship with former FBI Director James Comey, who is set to appear Friday in a closed-door interview with House Republicans.