SIMI VALLEY, Calif. (AP) — Emergency crews have found no threat after responding to the Ronald Reagan Library when a worker opened an envelope containing white powder.

Library spokeswoman Melissa Giller said authorities determined the substance was non-toxic.

The worker who opened the piece of mail and two others who reacted to the discovery were cleared.

An area where administrative staffers work was cordoned off, but the museum, cafe and other facilities remained open at the hilltop library about 35 miles northwest of downtown Los Angeles.

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