American counterterrorism officials are increasingly concerned that the most dangerous regional arm of Al Qaeda is trying to produce the lethal poison ricin, to be packed around small explosives for attacks against the United States.
For more than a year, according to classified intelligence reports, Al Qaeda’s affiliate in Yemen has been making efforts to acquire large quantities of castor beans, which are required to produce ricin, a white, powdery toxin that is so deadly that just a speck can kill if it is inhaled or reaches the bloodstream.
