VANCOUVER, Wash. (AP) -- Police reports show a Vancouver, Wash., man charged in connection with threatening letters containing white powder that were sent to members of Congress fell under FBI scrutiny after his wife told an officer that he laced the envelopes with a mixture of celery salt and corn starch.
The Oregonian reports (http://is.gd/EzrAUI) the FBI focused on Christopher Lee Carlson after a Vancouver police officer told them about a March 4 interview she had with Carlson's wife about Carlson's recent emotional turmoil.
On March 9, a federal grand jury in Portland indicted the 39-year-old nurse on charges that he mailed threatening letters to Republican House Speaker John Boehner of Ohio and Democratic Sen. Barbara Mikulski of Maryland.
The two counts arose from an investigation into the mailing of about 100 envelopes containing white powder. The U.S. attorney's office says the letters, postmarked in Portland, Ore., have tested negative for toxic substances.
Carlson is expected to be arraigned this week.