The world’s leading manufacturer of Bitcoin (BTC) mining equipment, Beijing-based Bitmain Technologies Ltd., has been under a national security probe in the U.S. for months now, as per a recent Bloomberg report.

Bitcoin mining is the process of using high-end computer systems to solve cryptographic functions, validate transactions, and add blocks to the network in return for BTC rewards.

While the U.S. leads the world in mining Bitcoin, it is China that is the global leader in manufacturing mining rig equipment.

Bitcoin miners across the globe, including those based in the U.S., are highly dependent on these Chinese suppliers. Notably, Bitmain Technologies is a supplier to American Bitcoin (Nasdaq: ABTC), as per the U.S. Securities and Exchange Commission (SEC).

American Bitcoin is a Bitcoin mining and treasury company that U.S. President Donald Trump‘s sons Eric Trump and Donald Trump Jr. founded in March 2025.

China’s Bitmain under national security probe in U.S.

Last year, a federal review under the Joe Biden administration flagged the use of Chinese-manufactured Bitcoin mining rigs near a military site in Wyoming due to “national security concerns.”

In July 2025, the Senate Intelligence Committee made a similar claim in a report and said the use of machines made by Bitmain, a company “with ties to” the Chinese Communist Party (CCP), near sensitive defense installations creates “disturbing vulnerabilities.”

The report also claimed that Bitmain personnel in China have the capability to remotely control these machines, posing “an unacceptable risk.”

An undisclosed federal investigation called “Operation Red Sunset,” led by agents of the U.S. Department of Homeland Security (DHS), also probed Bitmain equipment, Bloomberg cited a U.S. official and six other people familiar with aspects of the inquiry to report.

The probe aimed to inquire if these machines could indeed be remotely controlled for espionage or to sabotage the American power grid.

Federal officials in the U.S. have stopped Bitmain machines at the ports and at times pulled them apart to probe more. The sources didn’t reveal the findings to the publication.

The current status of Operation Red Sunset is unclear. A senior administration official said,

“The US government is concerned about threats of this nature and are constantly and vigilantly monitoring them.”

Bitmain denies national security threat allegations

Bitmain said it’s “unequivocally false” that the company can remotely control its Bitcoin mining machines from China. It “strictly complies with US and applicable laws and regulations and has never engaged in activities that pose risks to US national security,” the statement read. Bitmain claimed it’s not aware of the “Operation Red Sunset.”

The detentions of its machines were related to concerns raised by the Federal Communications Commission (FCC) but “nothing out of the ordinary was found,” Bitmain added.

The company also said it has “no connection to the Chinese government.”

American Bitcoin on its dealings with Bitmain

American Bitcoin “takes national security, grid stability and operation security extremely seriously,” said a company spokesman. He added that the company extensively tests hardware for security concerns and has found no vulnerabilities related to remote access.

The company’s rigorous security framework ensures that its mining operations would prevent threats to U.S. infrastructure.

American Bitcoin believes that when Bitmain’s machines “are deployed within modern industrial security standards, they do not present a credible risk to the United States power grid or to national security,” he added.

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Via https://www.thestreet.com/crypto/policy/homeland-security-probes-chinese-made-bitcoin-mining-equipment