Yahoo developed software that helped the US government search through its users’ incoming emails, Reuters reported.
The searches were conducted based on information US intelligence officials supplied, stated the report.
Citing former employees, the report said Yahoo was complying with a classified demand from the US government.
Hundreds of millions of Yahoo accounts were scanned on behalf of the NSA and FBI.
Reuters said it is not clear what the intelligence agencies were looking for, and it could not find out what data Yahoo handed over.
They also don’t know whether the NSA, FBI, or other government agencies went to other US-based email providers with a similar request.