SPOKANE, Wash. (AP) - Authorities say the person who left a bomb along a Martin Luther King Jr. Day parade route in downtown Spokane had mixed a chemical with shrapnel.
Spokane County Ozzie Knezovich told the Spokesman-Review that tests are being conducted to determine the chemical and whether it made the bomb potentially more deadly.
The bomb was found on a bench before the Jan. 17 parade started and was defused without incident. The FBI has said it was a sophisticated device that could have caused mass casualties.
Knezovich said Tuesday that the chemical could have been a compound used in rat poison. A common rat poison ingredient inhibits blood clotting.
Frank Harrill of the FBI's Spokane office says he couldn't comment on the chemical. The bomb has been sent for testing at the FBI laboratory in Virginia.
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