The INLA is the focus of a Paramilitary Crime Task Force operation taking place in Belfast involving more than 200 PSNI officers, police have confirmed.
Four men have been arrested; three under the Terrorism Act and a fourth on suspicion of human trafficking and controlling prostitution.
Police said 12 properties were searched in north, south and west Belfast as well as in Lisburn, Crumlin and Newtownabbey.
One of the properties was the west Belfast offices of the Irish Republican Socialist Party (IRSP) which is the political wing of the INLA.
The IRSP described the operations as "political policing".
Update on the significant policing operation in the greater Belfast area today. #endingtheharm pic.twitter.com/hMW3a7e72k
— PSNI (@PoliceServiceNI) April 13, 2018
Police have described it as a "significant policing operation" across greater Belfast.
A PSNI spokesman said officers were supported by their colleagues from NCA and HMRC.
"It represents the latest action by the Paramilitary Crime Task Force," the spokesman added.
Hundreds of Paramilitary Task Force @PoliceServiceNI officers involved in searches across greater Belfast pic.twitter.com/VVRBsDhNZu
— Bimpe Archer (@BimpeIN) April 13, 2018