Fenway Park will be targeted for a simulated “large-scale terrorist attack” with “active shooters” Sunday as federal agents and Boston cops practice their game plan for the unthinkable — and they’re looking for Red Sox fans who are willing to play themselves while they do it.

Law enforcement and Red Sox officials emphatically stated the first-ever exercise in the 104-year-old ballpark does not reflect on any active security concerns.

“It is not in any way indicative of deficiencies at the park,” said police spokesman Lt. Mike McCarthy.

“We wouldn’t want people to think an incident prompted us to do this,” added Red Sox spokeswoman Zineb Curran.

The Boston Police Department is hosting the June 12 drill, McCarthy said, and plans to put out a casting call for more than 100 volunteers to portray fans caught in a violent showdown between terrorists and police and Department of Homeland Security agents that will ?include realistic-sounding ?explosions and gunfire. This is the first time that the BPD has held a drill of this kind at Fenway Park, Curran said.

The BPD was looking for a large, open venue for its latest drill after using hospitals and hotels in the past. Both Fenway Park and TD Garden were offered up by their owners.

Curran said Red Sox Director of Security and Emergency Services Charlie Cellucci had been looking to hold an exercise on this scale at the stadium for some time. While Curran said she is “confident” in Red Sox security standards, the simulation will test the Red Sox’ personnel as well as the cops.

“The opportunity to participate in this is not just a test of the city’s preparedness but our own internal ones as well,” Curran said.

“It’s practice and preparation for a large-scale terrorist attack,” officer James Kenneally said. “The tech is being kept close to the vest, we don’t want to show our hand.”

McCarthy said the drill will be similar to one run in Brooklyn, N.Y., last month, which simulated active shooters with IEDs attacking a high school. Neither simulated terrorists nor police will be using live ammunition, McCarthy said, instead using paintball cartridges to determine when a participant has been “killed.” There will be simulated attacks both inside and immediately outside the park, McCarthy said.

Fenway Park will have its regular game day street closures from 9 a.m. to 1 p.m. and officers will be monitoring checkpoints to allow role players in while keeping passers-by out.

“It’s a very secure environment, a controlled environment,” McCarthy said.

Curran said the Red Sox would be reaching out to the public over the course of the week to alert people to the simulation, using media announcements and directly notifying neighborhood associations and other groups of the explosions and activity they can expect on Sunday.

“The last thing we would want is to alarm people in the neighborhood passing by, unaware of what was going on,” Curran said.

An $85,000 federal grant will cover most of the exercise’s costs, Kenneally said.

“The important thing is it gives us an understanding of what the capabilities of Fenway Park are and it allows all the parties involved to understand what their roles would be,” McCarthy said.

Firefighters and EMTs will also take part, and besides Homeland Security, members of the Army’s Armament Research, Development and Engineering Center will also use the simulation to test out their latest tech, McCarthy said.

“This is a more proactive step, learning capabilities, learning technology, learning what each other’s role will be in an emergency,” McCarthy said. “It comes down to sharing info and learning and working with other agencies.”

Anyone interested in taking part in the simulation is asked to email colm.lydon@pd.boston.gov.