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Before Walter Reed can be redeveloped into this, itll have to withstand an IED attack.ll have to withstand an IED attack.

At approximately 9 p.m. on Sunday, an improvised explosive device will explode at the former Walter Reed Army Medical Center. Shortly thereafter, a gunman will attack the Navy Yard. Wounded residents will be rushed to George Washington University Hospital.

But don’t worry, it’s all fake.

D.C.’s first responders are carrying out a multilocation exercise Sunday night into Monday morning to simulate terror attacks and practice responding to them. The party kicks off at Walter Reed—-the currently vacant site between Georgia Avenue and 16th Street NW that will soon be redeveloped into a mixed-use community—-around 9 p.m. with an IED explosion, followed by an an active-shooter simulation at the Navy Yard, home to an actual shooting last year where 13 people were killed. Then the action will move to GW Hospital for a medical response.

“We’re going to have fake casualties and fake injured people,” says Homeland Security and Emergency Management Agency spokeswoman Robyn Johnson. “We have volunteers in that role.”

The exercise will conclude around 9 on Monday morning.

So if you see emergency responders rushing around town this weekend, don’t freak out: It’s all for your simulated safety.

Rendering from Hines and Urban Atlantic