A 23-year-old man and a 22-year-old woman from Halifax have been arrested on suspicion of terrorism offences.
They were detained by counter-terrorism chiefs along with three other people, two from Birmingham and a 17-year-old boy from Nottingham earlier today.
All five are being questioned on suspicion of being members of a proscribed organisation (National Action) contrary to section 11 of the Terrorism Act.
Police say they are being held at a police station in the West Midlands.
The arrests were carried out by West Midlands Counter Terrorism Unit in conjunction with CTP North East and East Midlands CTIU.
A number of properties are being searched in connection with the arrests.