(CBS/AP) Spokane, Wash. - Kevin Harpham, a man previously tied to a white supremacist organization, was arrested Wednesday on charges that he left a sophisticated bomb along a Martin Luther King Jr. Day parade route in Spokane.
A clerk at the U.S. District Court in Spokane said Harpham is charged with one count of attempting to use a weapon of mass destruction and one count of knowingly possessing an improvised explosive device.
In a news release, the US attorney for the eastern district of Washington said a conviction on the first count carries a maximum penalty of life in prison, a $250,000 fine, plus up to five years of supervised release. The other charge could bring a maximum of 10 years in prison.
Workers found the bomb inside a backpack on Jan. 17, before the start of Spokane's MLK Jr. Day parade. It was defused without incident.
Federal and local law enforcement officers descended on a home near a rural town in Stevens County on Wednesday. Two T-shirts found with the bomb were tied to events in that area.
Officials for the FBI in Spokane, which is leading the search, declined to comment on the developments, but the agency has said the timing of the placement of the bomb raised concerns that racism was a motivation.
Officials for the FBI described the bomb as sophisticated and designed to produce mass casualties.
For weeks, the FBI had said nothing about possible suspects. But public opinion from the beginning focused on some of the white supremacist groups that have brought notoriety to the region in the past three decades. The area once served as headquarters for Richard Butler's Aryan Nations, whose members were lured by the small number of minorities.
Mark Potok of the Southern Poverty Law Center told the AP that Harpham was a member of the white supremacist National Alliance in 2004, although the organization - which tracks hate groups - wasn't certain when he joined or if he had left the group.
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