Senator Elizabeth Warren has reportedly asked the US Commerce Department to explain how it is handling potential national security risks tied to Chinese crypto mining giant Bitmain, following previous reports that the firm has been under federal scrutiny.
In a letter sent Thursday to Commerce Secretary Howard Lutnick, Warren requested documents and communications related to Bitmain, which manufactures a large share of the world’s Bitcoin mining equipment, Bloomberg reported on Friday.
In November last year, it was reported that US authorities had launched an investigation into Bitmain over potential national security risks. The probe, known as “Operation Red Sunset” and led by the US Department of Homeland Security, aimed to examine whether Bitmain’s ASIC machines could be remotely accessed for espionage or used to disrupt the US power grid.
According to Bloomberg, the probe remains unresolved, and its current status is unclear. National security investigations of this type can run for years without public disclosure or legal action.
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US scrutiny of Bitmain deepens
The scrutiny follows earlier actions, including halted shipments of Bitmain devices and a separate investigation into a related Chinese chip firm over alleged links to sanctioned Huawei.
In 2024, a federal review also flagged the use of its machines near a US military base as raising “significant national security concerns.”
In July last year, Bloomberg also reported that Bitmain is preparing to open its first US-based ASIC manufacturing facility, with chip production expected to begin in early 2026 and scale by year-end.
Cointelegraph reached out to Warren and Bitmain for comment, but had not received a response by publication.
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Trump-backed American Bitcoin buys Bitmain mining rigs
Bitmain’s machines are widely used in Bitcoin mining operations, including by American Bitcoin Corp., which counts Eric Trump and Donald Trump Jr. among its investors. The firm agreed last year to acquire 16,000 Bitmain rigs in a $314 million deal.
Warren’s letter also seeks details on any communications between Bitmain, the Trump family and Commerce officials, and asks what steps the department has taken to shield national security decisions from political influence.
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