WASHINGTON - Classified information was found at veteran American diplomat Robin Raphel's home, who came under investigation of the Federal Bureau of Investigation (FBI) after it intercepted the communication of a Pakistani official that indicated she might have been involved in providing secrets to the Pakistan government, The Washington Post reported Saturday, citing U.S. officials.

 The intercept triggered months-long surveillance Ms. Raphel, a former ambassador and assistant secretary of state, and eventually led the bureau to obtain a warrant to search her home in Washington; her office at the State Department was also searched.  But the post said it was unclear what form of communication was intercepted by the United States.

The newspaper cited one U.S. official, who spoke on condition of anonymity to discuss an ongoing case, said the bureau found classified information at Raphel’s home.

The New York Times first reported on the intercept and the lengthy surveillance of Raphel, 67, who has not spoke publicly since news of the investigation broke this month.

“Ambassador Raphel is a highly respected career diplomat who has dedicated her life to serving the United States and its interests,” Amy Jeffress, Raphel’s attorney and the former chief of the National Security Section in the U.S. Attorney’s Office for the District of Columbia, was quoted as saying by the Post. “She would never intentionally do anything to compromise those interests.

She, and we as her counsel, are cooperating with the investigation, and we are confident that she will be cleared of any suspicion.”    A spokesman for the Justice Department would neither confirm nor deny the existence of an investigation, according to the newspaper.

Raphel’s security clearances were pulled and her contract with the State Department was allowed to expire because of the investigation.

The search of Raphel’s home was one of several open steps by the FBI that indicated the investigation was at an advanced stage and agents were comfortable with some details about the case becoming public," the dispatch said.

Many FBI counterintelligence investigations never result in criminal charges, it said. Espionage cases involving Americans are rare and often difficult to prosecute because they involve classified material the government does not want made public.

Raphel is a well-known figure in diplomatic circles. She began her government career as a CIA analyst, according to a State Department biography. She served 30 years in the Foreign Service and retired from the State Department in 2005.

Her former husband, Arnold Raphel was the U.S. ambassador to Pakistan when he was killed in a 1988 plane crash with President Mohammad Zia ul-Haq.

Raphel returned to the State Department in 2009 to work as an adviser to Richard Holbrooke, who had been named by then-Secretary of State Hillary Rodham Clinton to the new post of special representative for Afghanistan and Pakistan.

Raphel also worked as a lobbyist for Cassidy & Associates, a Washington-based government relations firm, before returning to the government.