PORTLAND (WTAQ) - A federal grand jury is adding to the list of charges against a Washington state man accused of sending threatening letters to members of Congress.
The envelopes contained a white powder.
Christopher Lee Carlson now faces 18 felony charges. The list of charges grew longer when he was accused of sending threatening messages to offices of several Republicans, including U.S. Senator Ron Johnson of Wisconsin.
Carlson returns to federal court in Portland next Friday. All the letters were postmarked in Portland.
Tests for toxic substances were negative. The letters were first reported in February.