Former FBI Director James Comey slammed Attorney General William Barr for "echoing conspiracy theories" in an interview on CBS.

"Bill Barr on CBS offers no facts. An AG should not be echoing conspiracy theories. He should gather facts and show them. That is what Justice is about," Comey tweeted on Saturday.

Bill Barr on CBS offers no facts. An AG should not be echoing conspiracy theories. He should gather facts and show them. That is what Justice is about. — James Comey (@Comey) June 1, 2019

Barr spoke with CBS News after special counsel Robert Mueller delivered a roughly nine-minute statement about the investigation into Russian interference in the 2016 election.

In that interview, Barr contradicted the reasoning Mueller gave about why he did not make a determination on the question of whether President Trump obstructed justice. “I personally felt he could’ve reached a decision," Barr said during an interview with CBS on Thursday. Barr said Mueller “had his reasons for not doing it” but declined to explain. “I’m not going to, you know, argue about those reasons,” he said.

Mueller, both in his report and in his public statement, contended that he “did not make a determination as to whether the president did commit a crime” due to a Justice Department Office of Legal Counsel opinion that precludes a sitting president from being charged with a crime.

Barr disagreed with that reasoning. “The opinion says you cannot indict a president while he is in office, but he could’ve reached a decision as to whether it was criminal activity," he said. The attorney general also condemned Trump's critics and accused the media of ignoring surveillance activities carried out against Trump's 2016 campaign. "The media reaction is strange," he said. "Normally the media would be interested in letting the sunshine in and finding out what the truth is. And usually the media doesn't care that much about protecting intelligence sources and methods. But I do and I will."

Barr is looking into the origins of the counterintelligence investigation into Trump's campaign over misconduct concerns by some officials, including Comey, and has tasked U.S. Attorney John Durham with leading a review.

"I think the activities were undertaken by a small group at the top which is one of the, probably one of the mistakes that has been made instead of running this as a normal bureau investigation or counterintelligence investigation. It was done by the executives at the senior level, out of headquarters," he said.

Asked if he was talking about Comey or former FBI Deputy Director Andrew McCabe, Barr declined to be specific. "I'm just not going to get into the individual names at this point. But I just view that — I don't view it as a bureau-wide issue. And I will say the same thing for other intelligence agencies. And they're being very cooperative in helping us," he said.

Trump has accused Comey, who oversaw the beginning of the counterintelligence investigation into his 2016 campaign, of committing "treason," a crime that is punishable by death in the U.S. Barr said he disagrees with Trump's "treason" accusation as a legal matter.

Trump fired Comey from the FBI in May 2017.