"President Carter's message is notable for making no reference to the circumstances of Lord Mountbatten's death, " said a Foreign Office official.

BBC: Files show US-UK tensions over Northern Ireland in 1979

The story in the final edition of that day's paper had far fewer details, making only one passing reference to a phone message.

WSJ: Eight Charged With Phone-Hacking Offenses in U.K.

He had asked police in Puerto Rico and New York, where he lives part of the time, to investigate first, then went to the FBI after the message was posted with an apparent reference to the April 15 bombing at the Boston Marathon.

WSJ: Arrest for anti-gay Twitter threat in Puerto Rico

The most basic gesture and action is to archive a message that you have read or realize that you do not have to read but want to retain for reference.

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