The head of the U.S. military’s Central Command on Wednesday told a Senate hearing on the conflict against ISIS that he never asked for intelligence reports to be skewed to present a more positive view of military operations in Iraq and Syria.

General Lloyd Austin made the comments after the Pentagon’s inspector general confirmed last week that it had opened an investigation into allegations Central Command officials had suppressed intelligence.

Appearing before a Senate committee, Austin was asked by Sen. Angus King whether he ever ordered or even hinted to intelligence officers that they “sweeten” their reports to present a more positive view of the U.S. fight against the ISIS in Iraq and Syria.

“Absolutely not, Senator King,” Austin responded. “Absolutely not.”

A U.S.-led coalition is conducting air strikes in Syria and Iraq targeting the ISIS. The United States first started attacking the Islamist militant group inside Syria about a year ago, but has been unable to wrest its control from major cities there or in Iraq.

Analysts working for Central Command, which oversees the war in Syria and Iraq, say the leadership of their intelligence wing suppressed or rejected negative assessments of the U.S. position in the conflict against ISIS and al Qaeda, according to media reports.

A spokeswoman for the Pentagon’s inspector general on Friday said its office had opened an investigation to address whether there was any “falsification, distortion, delay, suppression, or improper modification of intelligence information.”

Austin, who has not been accused of any wrongdoing, told the Senate Armed Services Committee on Wednesday that his expectation is that he received “candid and accurate intelligence assessments from my staff.”

He also assured Sen. Claire McCaskill of Missouri that those who complained about their reports being distorted would not face retaliation.

“We’re going to cooperate fully and we’ll make sure that we abide by the spirit of this investigation,” Austin said. He assured the senators that once the investigation was complete, he would take appropriate action based on its findings.