Nvidia CEO Jensen Huang has admitted having an affair with a woman identified in a series of reports as a suspected Chinese spy, plunging the chip colossus into a crisis like none before in its three-decade history.

Huang disclosed the romantic relationship in a memo to employees on Sunday, saying the Nvidia board was launching an investigation. He had previously said there was nothing inappropriate about his relationship with the woman, who worked for a Singapore-based customer.

“I was unfaithful to my wife,” Huang, 63, said in the memo. “My actions hurt her and our children. There is no excuse for what I did. I am deeply sorry.”