A new report says the National Security Agency might have tapped Level 3 Communications‘ fiber-optic cables to eavesdrop on Yahoo and Google users.

While breaking through barriers at the Internet companies’ data centers would be a herculean task, the cables that connect those facilities are an easier target for the government. At least that’s what sources told The New York Times, specifically naming Level 3 as a company whose cables were likely exploited for information gathering. The Colorado-based company is the world’s biggest Internet backbone provider.

Yahoo and Google have both said that they are now encrypting the data that run from one data center to the next.

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