[WASHINGTON] Yahoo on Wednesday denied conducting mass email surveillance after a report alleging it built a special scanning program at the behest of US intelligence which sparked an outcry from privacy activists.
The report, which said the US internet giant had secretly scanned millions of emails to help American intelligence, was "misleading", Yahoo said in a statement.
"We narrowly interpret every government request for user data to minimise disclosure," the company said in a statement ot AFP. "The mail scanning described in the article does not exist on our systems."
The report Tuesday by Reuters news agency, citing former employees of the internet firm as sources, said Yahoo had built a custom program in 2015 which scanned all its emails to help US intelligence and the FBI.
According to the report, Yahoo's top security officer, who had been unaware of the program, quit after learning that the company had complied with the request.
Shortly after the report, Yahoo issued a brief statement which neither confirmed nor denied the claims.
"Yahoo is a law abiding company, and complies with the laws of the United States," the statement on Tuesday said.
The NSA and FBI declined to comment to AFP on the report.
The report was described by some activists as a "bombshell" which could, if proven true, reveal a new level of surveillance by the National Security Agency, which was roiled by disclosures in 2013 by former contractor Edward Snowden.
"There's still much that we don't know at this point, but if the report is accurate, it represents a new - and dangerous - expansion of the government's mass surveillance techniques," Bruce Schneier, a cryptographer and fellow at the Berkman Klein Center for Internet & Society who has clashed with the NSA over surveillance, said he was not surprised by the latest claims.
"The NSA is spying on the internet, they use different techniques," Mr Schneier told AFP.
The report nonetheless would be at odds with Yahoo's transparency report which claimed it received a relatively small number of US government requests in 2015.
Yahoo also backed Apple's effort to challenge a US government effort to force the iPhone maker to build a program to help decrypt a handset used by one of the shooters in a California shooting spree.
Julian Sanchez, a fellow at the Cato Institute and critic of NSA surveillance, said he was not persuaded by Yahoo's statement.
"Yahoo's meticulously worded statement not terribly comforting," Mr Sanchez said on Twitter.
"'Does not exist on our systems' sounds a hell of a lot like 'currently under this program'. DID it exist? Does it exist somewhere else?"
The report also suggested that other US tech companies may have received similar requests, but it was not immediately clear how these firms may have responded.
Facebook, in a statement to AFP, said it "has never received a request like the one described in these news reports from any government, and if we did we would fight it."