WASHINGTON-Yahoo has fired back at a report that accused the American multinational technology company of scanning customers’ emails for U.S. intelligence agencies, calling it “misleading.”

“We narrowly interpret every government request for user data to minimize disclosure. The mail scanning described in the article does not exist on our systems,” Yahoo said in an emailed statement to reporters Wednesday.

Reuters in a report Tuesday claimed that Yahoo, at the request of authorities, had designed custom software to scan all of its users’ emails for information of interest to U.S. intelligence agencies.

In the past, Yahoo had challenged orders for customer data, including in 2007 when the company fought and lost a directive to search customer accounts without a warrant.

Nevertheless, Reuters’ report revived concerns about court-approved surveillance programmes that companies aren’t allowed to disclose to the people using their services.

Last year, Yahoo modified an existing version of its email security programme to flag the appearance of a digital “signature” the U.S. had linked to a foreign terrorist group backed by another government, according to a report published Wednesday by The New York Times. Copies of any incoming email containing the signature were stored in Yahoo’s system and made available to the FBI. The Times quoted an unnamed government official, following up an earlier Reuters story that had revealed Yahoo’s email scanning activity without specifying what kind of information the government sought.

The revelations have conjured memories of a data-collection programme set up by the National Security Agency and major internet companies a few years ago under other court orders issued in secret, it was pointed out.

 That programme, called “Prism,” only became public knowledge in 2013 after former NSA contractor Edward Snowden leaked slides revealing that the government had been authorized to grab emails, videos and pictures stored by Google, Yahoo and Facebook, among other companies.

As with Prism, the U.S. government appears to have demanded Yahoo’s cooperation in an effort to sniff out terrorist threats and protect public safety. The government said Prism targeted the specific online accounts of foreigners.