N.S.A.’s intercepts exceed limits set by Congress

The National Security Agency intercepted private e-mail messages and phone calls of Americans in recent months on a scale that went beyond the broad legal limits established by Congress last year, government officials said in recent interviews.

Several intelligence officials, as well as lawyers briefed about the matter, said the N.S.A. had been engaged in “overcollection” of domestic communications of Americans. They described the practice as significant and systemic, although one official said it was believed to have been unintentional.