The active shooter drill was proposed by the crew of the USCG cutter Munro. (Pipa Escalante/KUCB)

The Coast Guard is teaming up with emergency personnel in Unalaska to practice their response to a mass shooting on the docks -- in one of the region’s busiest ports.

On Friday afternoon, a lone gunman will approach the Coast Guard cutter Munro at its berth in the City Dock and begin firing off blanks.

"Police will respond, Fire and EMS will take care of the injuries along with the Coast Guard crew and transport the patients to the simulated medical facility," says fire chief Zac Schasteen. "Once that’s done, the Ports Department will start notifying the industrial partners -- meaning the folks that have an interest over at the dock."

Fuel suppliers and shipping personnel may conduct searches at their own facilities. They’ll be on the lookout for bombs that could pop up during an attack on the port.

The marine industry’s conducted similar exercises in the past. And Unalaska’s police department has been called to check on reports of gunfire from at least one fishing boat.

But mounting a full-scale drill was the Coast Guard’s idea. The agency is responding to a string of shootings on military bases -- including one of their own. A few years ago, a disgruntled Coast Guard employee killed two coworkers at a communications office in Kodiak.

Public affairs officer Diana Honings says all Coast Guard personnel should know how to handle a gunman -- even those who primarily work at sea, aboard cutters.

"People rotate very often," Honings says. "So we get new people in and we need to train them for these kind of scenarios. We are practicing the tactics -– and I can’t go into the law enforcement stuff for operational security. But we do have to ensure that everyone is aware of what they need to do in that type of situation."

That includes reaching out to local law enforcement.

Unalaska’s fire chief expects to iron out some differences in terminology -- and work on systems for making radio calls to the Coast Guard. Beyond that, Schasteen says it’s a rare opportunity for volunteer firefighters and EMTs to stretch their skills.

"In Unalaska, we see a number of traumatic calls -- primarily industrial trauma relating to the fishing industry and support services," Schasteen says. "Fortunately for us, what we don’t see a lot of is ballistic injuries."

Schasteen’s planning to keep it that way. He says police officers will trade in their weapons for non-functional rubber versions during the drill. And the gun that the active shooter will be using isn’t capable of firing live rounds.

Some parts of the City Dock may be off-limits during the drill. The exercise is expected to start mid-afternoon and last about an hour.