The Pentagon is not responding to harsh criticism in a report from congressional Republicans that concluded that intelligence assessments produced by U.S. Central command were routinely edited by higher-ups to present a more optimistic picture of progress in the war against the Islamic State.

A Pentagon spokesman says the department will not have any comment on the specific allegations in the report while it awaits the results of its own investigation by the independent Department of Defense inspector general, who is looking at the same issue of whether intelligence was "cooked" by senior officers over the objection of Central Command analysts.

"That investigation is ongoing, and we will take no action or make any comment that could appear to influence the IG's work," said Pentagon spokesman Lt. Cmdr. Patrick Evans.

The House task force noted it "did not receive access to all the materials it requested," and said it was also depending on the DoD IG to "review and assess further documents and internal emails, as well as the statements of many additional DoD employees, and to fully investigate any allegations of reprisals."

The central question is whether senior military officers changed the intelligence with the intention of improving it, or slanting it.

The congressional report released Thursday said during the time period it evaluated, it found that Central Command produced intelligence that was "significantly more optimistic than that of other parts of the intelligence community, and typically more optimistic than actual events warranted."

The senior leaders, who were not named in the report, told congressional investigators that they believed the changes they made were "productive," and were based on their "unique knowledge of the operational situation based upon their insight from senior-level CENTCOM meetings and interactions."

But the report concluded there was "no justifiable reason why operational reporting was repeatedly used as a rationale to change the analytic product, particularly when the changes only appeared to be made in a more optimistic direction."

Without commenting on the specific findings of the congressional report, the Pentagon's statement noted that the intelligence community "routinely provides a wide range of assessments."

"Experts sometimes disagree on the interpretation of complex data," Evans said. "The Department of Defense welcomes healthy dialogue on these vital national security topics."