Senator Elizabeth Warren sent a letter to Commerce Secretary Howard Lutnick seeking documents about Bitmain Technologies Ltd., a Beijing-based Bitcoin (BTC) mining hardware manufacturer under federal investigation for potential national security risks.
The inquiry follows a $314 million Bitmain equipment purchase by American Bitcoin, a mining company backed by President Donald Trump's sons.
Warren requested information about communications between Bitmain, the Trump family, and the Commerce Department, as well as actions taken to "insulate" national security decisions from firms with Trump business ties.
The letter references Operation Red Sunset, a Department of Homeland Security investigation examining whether Bitmain machines could be remotely controlled for espionage or to sabotage the U.S. power grid.
Federal Investigation Examines Remote Control Risk
Bloomberg reported in November 2025 that Operation Red Sunset began under the Biden administration, with investigators testing Bitmain equipment at U.S. ports.
A Senate Intelligence Committee report in July 2025 concluded that Bitmain devices "can be forced by the PRC to turn over data" under China's national security law.
A May 2024 federal review ordered divestment of a mining facility near Wyoming's Francis E. Warren Air Force Base, citing "significant national security concerns" about foreign-sourced equipment. The current status of Operation Red Sunset remains unclear.
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Trump Family Mining Venture Uses Bitmain Equipment
American Bitcoin executed a contract in August 2025 to acquire 16,000 Bitmain mining rigs for $314 million, paid in pledged Bitcoin rather than cash, according to SEC filings. The company plans to operate 76,000 machines across the U.S. and Canada.
A spokesman for American Bitcoin told Bloomberg the company conducted security tests and found no vulnerabilities allowing remote access. Bitmain stated it "strictly complies with U.S. laws" and has no knowledge of Operation Red Sunset.
The Commerce Department did not immediately respond to requests for comment. Democrats hold minority status in the Senate and cannot compel a response.
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