Nearly 100 people were evacuated from a facility in Washington state.

TACOMA, Wash. (AP) – A Postal Service center was evacuated Tuesday after a preliminary test indicated white powder found among some envelopes might be toxic. Later tests found no signs of a harmful biological substance.

State and fire department officials said tests by the Army National Guard and state health officials found no signs of any biotoxin. Samples will be sent to the Centers for Disease Control and Prevention for review.

Nearly 100 people were cleared from the building after the powder was found about 12:45 a.m. on a table where mail is processed, fire Capt. Jolene Davis said.

Elsewhere, six Postal Service workers were taken to a hospital in Fort Myers, Fla., after they were exposed to an unknown white powder when they opened a mail container unloaded from a FedEx plane that arrived from Memphis, Tenn.

One of those taken to a hospital complained of a burning sensation in his nose, said Paul Filla, a spokesman for the Lee County Emergency Management Service.

The powder was being tested, Southwest Florida International Airport spokeswoman Laska Ryan said. Students at three elementary schools near the airport were kept inside for more than three hours as a precaution.

AP-ES-04-22-03 1732EDT