FBI investigates suspicious letters to election officials nationwide

Federal authorities are probing suspicious mailings containing unknown substances sent to state election offices and congressional addresses.

The FBI and U.S. Postal Inspection Service are investigating suspicious letters mailed to state election officials and congressional offices across the country. Deputy Chief Inspector Brendan Donahue said some letters contained unknown substances and were sent to secretary of state offices and related election divisions nationwide.

Congressional offices were among the targets. Senator Chris Murphy's office received a letter with a suspicious substance that was intercepted, and Senator Alex Padilla's office also received a suspicious mailing. The Senate sergeant at arms notified congressional staff of the investigation.

Election officials in Louisiana and Oklahoma reported receiving packages with white powder. Testing in Louisiana found no harmful substances and no injuries occurred. The Oklahoma State Election Board was evacuated after discovering suspicious white powder in an envelope. Federal officials said they have intercepted some letters and are working to identify responsible parties.