details were given. 

 The US declared NCRI (National Council of Resistance of Iran) a terrorist organization. NCRI is the political wing of the armed MKO (or People's Mujahedeen.) NCRIs offices in the US were closed and it became illegal to contribute money to the group. At the moment, this will hurt the US, as  MKO and NCRI had a network of agents inside Iran that were passing information to American intelligence agencies. Apparently, cracking down on MKO/NCRI was partly due to the extremist politics of the group. Founded by communists and other radicals before the 1979 revolution, MKO supported the revolution against the shah, but then lost a power struggle with the Islamic conservatives after the revolution.