WASHINGTON - A letter addressed to Mississippi Senator Rocker Wicker was laced with ricin, a deadly poison.
Senate Majority Leader Harry Reid confirmed to ABC News that Capitol offices were on high alert. He referred questions to Capitol Police.
ABC News also reported the letter was stopped at a mail processing facility.
Aides in Wicker's office emphasized to ABC News that at no point did the senator's office evacuate or close because of the threat.
"Once we get information from Capitol Hill police, we will send out more," an aide to Wicker said Tuesday evening.