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... The latest packages were sent to elections officials in Georgia, Indiana, Kentucky, Massachusetts, Missouri, New York and Rhode Island. Mississippi authorities reported a package was delivered there Monday, and the Connecticut Secretary of State's office said the FBI alerted it of a package that was intercepted.

The FBI is collecting the packages, some of which contained "an unknown substance," agency spokesperson Kristen Setera in Boston said in a statement.

"We are also working with our partners to determine how many letters were sent, the individual or individuals responsible for the letters, and the motive behind the letters," she said.

"As this is an ongoing matter we will not be commenting further on the investigation, but the public can be assured safety is our top priority." ...