Sen. Bernie Sanders on Monday warned that the Trump administration’s targeting of Federal Reserve Chairman Jerome Powell for criminal investigation was part of a broader pattern of intimidation aimed at quelling dissent.

In a prepared statement, Sanders (I-Vt.) acknowledged that he had his own disagreements with Powell, a conservative Republican who was first appointed by President Donald Trump to be chairman of the Federal Reserve in 2017.

However, Sanders said political disagreements had nothing to do with the Department of Justice launching a criminal probe of Powell.

“In a democracy, debate and disagreement are normal,” Sanders said. “But Donald Trump does not ‘disagree’ with his opponents. In his pursuit of absolute power, he attempts to destroy anyone who stands in his way. He’s actively prosecuting Powell not because the Fed chair broke the law, but because he won’t bend the knee to Donald Trump.”

Sanders noted that Powell was only the latest target of the Trump administration’s vindictive retribution.

“When Sen. Mark Kelly (R-Ariz.) spoke out against Donald Trump’s authoritarian rhetoric and threats toward political opponents, Trump didn’t agree,” Sanders explained. “He had his Defense Department investigate Kelly for misconduct and threatened to have him executed.”

Sanders also pointed to the prosecutions of New York Attorney General Letitia James and former FBI Director James Comey, as well as his threats against assorted other critics, as evidence that Trump seeks to “intimidate and destroy… as part of his march to authoritarianism.”

“We must not allow our great country, the United States of America, to become an authoritarian society,” Sanders concluded. “Trump’s persecution of his political opponents must end.”

The co-chairs of the Not Above the Law coalition–Lisa Gilbert, co-president of Public Citizen; Praveen Fernandes, vice president of the Constitutional Accountability Center; Kelsey Herbert, campaign director at MoveOn; and Brett Edkins, managing director for policy and political affairs at Stand Up America—also denounced the investigation into Powell as politically motivated on Monday, while arguing it was part of an effort to stifle dissent in the US.

“Whether targeting federal judges, members of Congress, civil society organizations, or now the chair of the Federal Reserve, Trump weaponizes the full force of government against anyone who won’t submit to his will,” they said. “Undermining the Federal Reserve threatens Americans’ jobs and savings, and our nation’s economy.”