WASHINGTON — A memo sent to all National Mall employees about the Washington Monument’s elevator says the problems may have been the result of human error.

ABC7 reports the memo indicated the elevator key was found in between operating and inspection mode, which could cause the elevator to stop working.

Last week, reports surfaced that the elevator broke down several times prior to its May 12 re-opening.

The Saturday before the opening, the elevator trapped a park employee inside and stopped working for a time later the same day. The next day another malfunction occurred.

No visitors were trapped inside. However, 60 people were evacuated from the 555- foot structure using the stairs. Spokeswoman Carol Johnson said the visitors were on the observation level 500 feet up on May 14 and had to walk down nearly 900 steps.

On Monday, ABC7 cited the memo when reporting the key that may have caused the problems was removed.

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