NSF terrorists are the first enemy JC Denton faces in the game. Alex Jacobson cautions JC that the NSF are "everywhere". During their first encounters they are armed with 10mm pistols, but as JC advances through New York, they become armed with better weapons, such as sawed-off shotguns and assault rifles. Three even have flamethrowers; one is under Castle Clinton, while the other is in Battery Park's subway station, the third in the Helicopter Station. They use LAMs as grenades, but very few are equipped with one. Additionally, some of them employ the use of Dobermans.
NSF terrorists are noticeably somewhat weaker than other grunt-type enemies, with only 75 health instead of 100 health, as well as worse aim and reflexes, as they are not professionals.
NSF terrorists disappear after clearing the LaGuardia Airport, except for two in the Majestic 12 complex beneath UNATCO Headquarters. These two terrorists were imprisoned; one of them (Miguel), depending on JC's actions, survives. The other is found dead in his cell, with a medkit.
Despite the add-on eyewear on the ski masks, their models have eyes.