House Intelligence Committee Chairman Devin Nunes, R-Calif., said the FBI has not responded to a March 15 letter asking the agency to turn over documents it has related to surveillance reports which may have incidentally captured the identities of some U.S. citizens last fall.

"I'll tell you, NSA is being cooperative," Nunes said. "But, you know, so far, the FBI has not told us whether or not they're going to respond to our March 15 letter which is now a couple of weeks old."

In that letter, the committee asked the FBI, CIA and NSA for a complete list of persons' names who had their identity improperly revealed as a part of any foreign surveillance in the last half of 2016. It also asks to understand how widely those identities may have been disseminated.

Nunes spoke to reporters just after briefing White House officials that he had acquired new intelligence reports showing some members of the Trump transition team were also incidentally collected during surveillance.

Whether the identities were "unmasked" in the reports is now a matter of debate between Chairman Nunes and his ranking counterpart on the Committee, Adam Schiff, D-Calif.

In a rebuttal press conference, Schiff said that most of the intelligence reports that Nunes described to him still had masked names, but the identities could be discerned from the context of the conversation.

Already known was that Michael Flynn's name was unmasked in a surveillance report of a phone conversation between Flynn and Russian Ambassador Sergei Kislyak. Parts of that report were then leaked to media outlets, and forced Flynn's resignation as national security adviser to President Trump. The conversation happened in late December of 2016, when Flynn was still only a member of the Trump transition team.

Much earlier on Wednesday, Nunes said he was concerned because the number of unmaskings "definitely goes beyond what happened to General Flynn." Nunes also made clear he thought the intelligence reports he read contained real foreign intelligence value.

The March 15 letter, signed by both Nunes and Schiff, expressed concern that the intelligence community may have strayed from "robust minimization procedures" that are intended to protect the identities of U.S. persons whose identity might accidentally be a part of some conversation by foreign entities who were under surveillance.