(WASHINGTON) -- Attorneys for an IRS whistleblower have informed key members of Congress that their client, who claims to have information suggesting the Biden administration could be mishandling the investigation into President Joe Biden's son, Hunter Biden, has been removed from the probe into the president's son.
According to a letter obtained by ABC News, the whistleblower's attorneys on Monday notified several House and Senate Committee chairmen, both Democrats and Republicans, that their client -- along with his "entire investigative team" -- had been removed from the probe.
The attorneys wrote in the letter that the whistleblower had been "informed the change was at the request of the Department of Justice."
"[T]his move is clearly retaliatory and may also constitute obstruction of a congressional inquiry," the letter reads.
A DOJ spokesperson told ABC News in a statement, "The Department cannot comment on the matter. As to any investigation of Hunter Biden, as the Attorney General has said that investigation is being handled by U.S. Attorney David Weiss, who has full authority to make investigative decisions and to bring charges in any jurisdiction as he deems appropriate. I refer you to U.S. Attorney Weiss for any questions concerning his investigation."
Weiss' office did not immediately respond to a request for comment.
ABC News previously reported that the lawyer for the IRS whistleblower said in a letter that their client is an IRS criminal supervisory special agent "who has been overseeing the ongoing and sensitive investigation of a high-profile, controversial subject since early 2020 and would like to make protected whistleblower disclosures to Congress."
The letter does not name Hunter Biden specifically, but lawmakers have been made aware he is the "high profile, controversial" subject that the lawyer is referring to.
While the letter refers to preferential treatment that Hunter Biden has allegedly received, there are no specific examples provided to support the accusations.
Weiss, a Trump-era appointee, has been leading the investigation into the younger Biden and his tax affairs since 2018.