(CNN) -- Recent assertions by European media outlets that the National Security Agency tapped tens of millions of phone calls in Europe are "completely false," NSA chief Gen. Keith Alexander told the House Intelligence Committee on Tuesday afternoon. He said that the media outlets misinterpreted documents that were leaked. He said the NSA legally collected metadata from some phone calls, and the rest of the metadata came from U.S. allies. "To be perfectly clear, this is not information that we collected on European citizens. It represents information that we, and our NATO allies, have collected in defense of our countries and in support of military operations," Alexander said.