WASHINGTON — Federal prosecutors have for months been using a grand jury to investigate former FBI deputy director Andrew McCabe — an indication the inquiry into whether he misled officials exploring his role in a controversial media disclosure has intensified, two people familiar with the matter told the Washington Post.The grand jury has summoned more than one witness, the people said, and the case is ongoing. The people declined to identify those who had been called to testify.The presence of the grand jury shows prosecutors are treating the matter seriously, locking in the accounts of witnesses who might later have to testify at a trial. But such panels are sometimes used only as investigative tools, and it remains unclear if McCabe will ultimately be charged.A spokesman for the U.S. attorney’s office in the District of Columbia, which has been handling the investigation, declined to comment.Michael Bromwich, a lawyer for McCabe, said in a statement after this story was published online that he had been confident McCabe would not be charged, absent "inappropriate pressure from high levels of the Administration.""Unfortunately, such pressure has continued, with the President targeting Mr. McCabe in numerous additional tweets," Bromwich said. The lawyer also raised questions about the timing of the news report on the grand jury."Today’s leak about a procedural step taken more than a month ago — occurring in the midst of a disastrous week for the President — is a sad and poorly veiled attempt to try to distract the American public," Bromwich said. "We remain confident that a thorough review of the facts and circumstances related to this matter will demonstrate that there is no basis on which criminal charges should be brought."The investigation into McCabe is as politically charged as they come, and a decision to prosecute him — or not — will draw significant criticism either way.McCabe — who briefly took command of the FBI after James Comey was fired last year — has been a frequent target of criticism from President Donald Trump. His comments have offered significant support for McCabe’s argument that he is being treated unfairly and the examination of him is tainted by partisanship.