The founder of the protest group that interrupted Federal Reserve Chair Jerome Powell’s speech in New York on Thursday called him a “climate criminal,” arguing he could be doing more to regulate banks that are financing fossil fuel investments.

“Jerome Powell is a climate criminal,” Michael Greenberg, the founder of Climate Defiance, said in an interview after protesters took to the stage at an Economic Club of New York luncheon moments before the Fed chair was set to speak.

“The Fed actually has the power to regulate these banks and significantly reduce fossil fuel financing, and yet they sit around and fiddle as the world burns,” Greenberg said.

A Fed spokesperson declined to comment.

Powell was escorted out of the room as the demonstrators chanted arm in arm and held up a banner before the audience. They were then removed from the event, and Powell returned to deliver his remarks. Greenberg said they were not placed under arrest.

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The Fed chair outlined his thoughts on the central bank’s role in climate policy in a speech earlier this year, arguing it “does have narrow, but important responsibilities regarding climate-related financial risks.”

“The public reasonably expects supervisors to require that banks understand, and appropriately manage, their material risks, including the financial risks of climate change,” Powell said in the Jan. 10 speech.

“But without explicit congressional legislation, it would be inappropriate for us to use our monetary policy or supervisory tools to promote a greener economy or to achieve other climate-based goals,” he said.

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