Protesters in Seattle often deploy a tactic known as the “sleeping dragon” in which they lay down in the street to block traffic with their arms linked while inside a piece of PVC tubing. The tactic makes it difficult for police to clear the street and make arrests.

Sometimes protesters in sleeping dragons are handcuffed to one another inside the tubing, which can be encased in concrete — or wrapped in chicken wire and duct tape, as was the case on Tuesday morning when people opposing immigration policies employed the technique while lying in the street at Second Avenue and Madison Street.

Simply cutting off the tubing runs the risk of injuring protesters, slowing the removal so much that it can take six or more hours to clear the street and take the protesters into custody.

But members of the Seattle PD’s new Apparatus Removal Team (ART) were able to  separate the nine protesters Tuesday and arrest them in about an hour and a half, the Seattle Times reports.

Seattle police spokesman Sgt. Sean Whitcomb said members of  ART are specially trained officers who have the knowledge, experience and equipment to cut through plastic and metal without hurting protesters. Because sleeping dragons vary in composition, the team relies on different tools, he said.