Washington (CNN) The intelligence community inspector general is forcefully pushing back against assertions made by President Donald Trump and several Republican lawmakers about the whistleblower complaint that has rocked Washington in recent weeks.

In a rare statement released Monday , the inspector general addressed a false claim pushed by Trump and some of his allies on Capitol Hill, including House GOP leader Kevin McCarthy of California and Sen. Lindsey Graham of South Carolina, that the whistleblower lacked firsthand knowledge of the conduct outlined in the complaint and therefore the allegations were based on "hearsay." But the statement from the inspector general made clear that the whistleblower was not simply communicating secondhand knowledge.

"The whistleblower stated on the form that he or she possessed both first-hand and other information," the statement read. "The ICIG reviewed the information provided as well as other information gathered and determined that the complaint was both urgent and that it appeared credible. "

The statement clearly says the whistleblower had "direct knowledge of certain alleged conduct" and that Intelligence Community Inspector General Michael Atkinson obtained additional information during his preliminary review that supported other allegations in the complaint not based on firsthand knowledge, including Trump's July 25 phone call with Ukrainian President Volodymyr Zelensky.

"As part of his determination that the urgent concern appeared credible, the Inspector General of the Intelligence Community determined that the Complainant had official and authorized access to the information and sources referenced in the Complainant's Letter and Classified Appendix, including direct knowledge of certain alleged conduct, and that the Complainant has subject matter expertise related to much of the material information provided," the statement says.

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