Pete Buttigieg on Thursday responded to the release of the redacted version of Special Counsel Robert Mueller's report on whether President Donald Trump colluded with Russia.

“The Mueller report is a disturbing if not completely surprising collection of evidence that shows a president putting his own interests ahead of the country's,” Buttigieg, the mayor of South Bend, Indiana, said in a tweet. “Today again demonstrates why we need to change the channel in 2020.”

Buttigieg and California Senator Kamala Harris were the only Democratic presidential candidates to weigh in on the report as of Thursday evening.

Trump continued to insist that the 448-page report cleared him of any wrongdoing.

“As I have been saying all along, NO COLLUSION – NO OBSTRUCTION!” Trump tweeted.

White House adviser Kellyanne Conway told reporters that the report gave Trump a “clean bill of health.”

“It should make people feel really great that a campaign I managed to its successful end did not collude with any Russians,” she said. “We're accepting apologies today, too, for anybody who feels the grace in offering them.”

Democrats and analysts, however, disagreed, noting that Mueller wrote that he had found “substantial evidence” that Trump fired FBI Director James Comey due to his “unwillingness to publicly state that the president was not personally under investigation.”

New York Representative Jerry Nadler, chair of the House Judiciary Committee, said in a press conference that the report outlines “disturbing evidence” that Trump engaged in obstruction of justice. He also called on Mueller to testify before his committee.

(Related: Trump says he would like to run against Pete Buttigieg.)