The U.S. Department of Homeland Security said over the weekend it has “no reason to doubt” statements from Apple Inc., Amazon.com Inc.’s AWS and Super Micro Computer Inc. and others denying that some of their servers were compromised by Chinese spy chips.

“The Department of Homeland Security is aware of the media reports of a technology supply chain compromise,” the agency said in a statement Saturday. ”At this time we have no reason to doubt the statements from the companies named in the story.”