The White House on Friday moved to block a 3 million US dollars acquisition of aerospace and defense assets by U.S. photonics firm HieFo Corp, citing risks linked to China and national security.

The decision targets HieFo’s 2024 purchase of New Jersey-based Emcore’s chips business and indium-phosphide wafer-fabrication operations. President Donald Trump, in an official order, stated that the company is “controlled by a citizen of the People’s Republic of China” and may take actions that threaten U.S. security. The order did not identify the individual or outline the specific risks.

Under the directive, HieFo must divest all interests in the Emcore assets within 180 days, effectively nullifying the deal. The Treasury Department confirmed that the Committee on Foreign Investment in the United States had flagged a national security concern during its review, without providing further detail.

HieFo was co-founded by Genzao Zhang, a former Emcore vice president of engineering, and Harry Moore, who previously served as Emcore’s senior sales director, according to LinkedIn profiles. At the time of the acquisition, Emcore was publicly traded but has since gone private.

Neither HieFo nor Emcore had issued a public response as of Friday evening. The move adds to a series of U.S. interventions on transactions involving firms with potential ties to Chinese stakeholders.