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

The security expert, Yossi Appleboum, provided documents, analysis and other evidence of the discovery following the publication of an investigative report in Bloomberg Businessweek that detailed how China's intelligence services had ordered subcontractors to plant malicious chips in Supermicro server motherboards 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.