It was found on letters sent to president , New York state , animal control group . In a separate incident , ricin is also found on letter to military base . One front of the FBI investigation advanced Friday in Texas , where authorities searched the home of a man in New Boston in connection with the threatening letters to Obama and Bloomberg . FBI on letter sent to the CIA .
It was found on letters sent to president , New York state , animal control group . In a separate incident , ricin is also found on letter to military base . FBI on letter sent to the CIA .