A major U.S. telecommunications company discovered manipulated hardware from Super Micro Computer Inc. in its network and removed it in August, according to a security expert working for the telecom company, in fresh evidence that critical technology components bound for the U.S. had been tampered with in China.

The security expert, Yossi Appleboum, provided documents, analysis and other evidence of the discovery following the publication of an investigative report by Bloomberg Businessweek that detailed how China's intelligence services had ordered subcontractors to plant malicious chips in the motherboards of Supermicro servers, made by Super Micro, over a two-year period ending in 2015.

Appleboum previously worked in the technology unit of the Israeli Army Intelligence Corps and is now co-chief executive officer of Sepio Systems in Gaithersburg, Maryland. His firm specializes in hardware security and was hired to scan several large data centers belonging to the telecommunications company. Bloomberg is not identifying the company due to Appleboum's nondisclosure agreement with the client.