Special counsel Robert Mueller s final report on Russian interference in the 2016 election is between 300 and 400 pages long, raising questions about the accuracy of the short summary Attorney General William Barr sent to Congress on Sunday.

The Justice Department had been cagey about the length of Muellers report this week, with an official only telling reporters on Sunday that the document was substantial. But on Thursday, a Department of Justice official confirmed to HuffPost that the report is more than 300 pages, and a DoJ official confirmed to CNN that it is between 300 and 400 pages, not counting exhibits.

Muellers team reportedly issued more than 2,800 subpoenas, interviewed more than 500 witnesses and executed nearly 500 search warrants, amassing thousands, if not millions of documents and pieces of evidence, according to The Associated Press .

The page count suggests the report will be fairly comprehensive, and raises questions about Barrs four-page letter on the report, which quoted only a few dozen words from the actual document. Barrs letter was meant to reflect the principal conclusions of the Mueller report, which left open the question of whether or not President Donald Trump obstructed justice.

Barr and Deputy Attorney General Rod Rosenstein, Barrs letter said, concluded that the evidence developed during the Special Counsels investigation is not sufficient to establish that the President committed an obstruction-of-justice offense. But theres reason to wonder if Barrs conclusion may have been preordained. Less than a year before taking over at the Justice Department, he authored an unsolicited 19-page memo questioning whether Mueller should even be investigating obstruction in the first place.

Muellers core premise that the President acts corruptly if he attempts to influence a proceeding in which his own conduct is being scrutinized is untenable, Barr wrote in the 2018 memo . He argued that the president would not be transgressing any legal limitation if he exercised his supervisory authority over cases dealing with his own interests: It may be in some cases politically unwise; but it is not a crime.

Some of these questions may be settled soon: Barr has agreed to testify before the House Judiciary Committee, The Wall Street Journal reports.

The House voted 420-0 earlier this month in favor of a resolution calling for Muellers report to be made public, which even Trump said he supports . On Monday, Senate Majority Leader Mitch McConnell (R-Ky.) blocked a similar measure from reaching a vote.