Senate Majority Leader Harry Reid says a letter containing ricin or another poison was sent to the office of Sen. Roger Wicker of Mississippi.
In brief remarks to reporters in the Capitol, Reid did not say when the letter was sent. It's customary for mail addressed to congressional offices to be screened at an off-site facility.
Sen. Mary Landrieu also confirmed a letter containing poison had been to a sent to a senator. She said lawmakers were informed of the fact at a closed-door briefing about the Boston Marathon bombings.