Eleven times in three days, hazmat crews have responded to reports of white powder found, often accompanied by a note threatening an attack if the US begins a war in Iraq or expressing support for Osama bin Laden.

On Monday, police and firefighters responded to white powder reports at seven locations around the city -- six of them in West Seattle -- causing the evacuation of dozens from a post office at one site.

In one of the cases on Monday, a message packaged with powder said "I'm an American. I hate America and I love Osama bin Laden," eyewitness Robert Strong told KIRO 7 Eyewitness News.

The $5,000 reward will be paid to whoever provides information leading to the arrest and charging of a suspect or suspects in the case, police said.

People with information are urged to call (206) 233-2666.

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The latest in the recent series of "powder" scares in Seattle happened Wednesday with some downtown streets blocked off for about an hour at midday after a man was spotted sprinkling orange dust in the street. A city hazardous-materials crew determined there was no threat.

Previous Stories: March 19, 2003: White Powder Scare In Downtown Seattle March 17, 2003: Series Of White Powder Scares In Seattle March 4, 2003: White Powder Scare At Seattle Post Office