WASHINGTON (AP) -- FBI Director Robert Mueller is cautioning Congress to give careful consideration before making any changes to the National Security Agency programs for mass collection of people's phone records and information from the Internet.
In an appearance before the Senate Judiciary Committee, the FBI director says there are 10 or 12 cases in which the phone records program contributed to breaking up terrorist plots.
Mueller says communications capabilities of terrorists are their weakest link.
The FBI director said that any narrowing of NSA programs would be, in his words, "taking the dots off the table" and said it's a question for Congress to address.
Mueller made the comments in response to questions from Judiciary Committee Democratic Sen. Patrick Leahy of Vermont and Democratic Sen. Dianne Feinstein of California.