A letter addressed to President Barack Obama containing a “suspicious” substance tested positive for the deadly poison ricin, the Federal Bureau of Investigation said Wednesday.
In a statement, the FBI said the investigation into the letter sent to Obama and another sent to Senator Roger Wicker was ongoing, adding there was “no indication of a connection” to the Boston Marathon bombings.
In an intelligence bulletin obtained by The Associated Press, the FBI said the letters both say: “To see a wrong and not expose it, is to become a silent partner to its continuance.” Both letters are signed, “I am KC and I approve this message.”
The letter to Obama was discovered at the remote facility which is used to screen White House mail on Tuesday, the same day authorities said a letter was sent to Senator Roger Wicker which was laced with ricin, a deadly poison.
Secret Service spokesman Edwin Donovan said the agency, which protects the president and his family, was working closely with the U.S. Capitol Police and the Federal Bureau of Investigation to trace the origins of the letter.
Tensions have been high in Washington and across the U.S. since the deadly bombings on Monday at the Boston Marathon that killed three people and injured more than 170.
The episode also recalled the mysterious series of letters laced with anthrax that were sent to lawmakers and some journalists following the September 11 attacks in 2001 which killed five people and sickened 17 others.