FAIRFAX COUNTY, Va. (DC News Now) — The Fairfax County Police Department said a U.S. Park Police (USPP) officer died after another U.S. Park Police officer shot him early Sunday.

Police said that at about 12:20 a.m., they responded to the 1700 block of Old Meadow Road in McLean for the report of a person who had been shot.

The caller told officers that a man was unintentionally shot inside of an apartment. The man died at the scene.

He was identified as 22-year-old Jesse Brown Hernandez of McLean.

Police found that Alexander Roy, 25, of McLean, was attempting to dry fire a firearm when he shot Hernandez.  

Dry firing is the practice of shooting a firearm without ammunition in the chamber. Roy unintentionally shot the firearm he thought was unloaded and fatally shot Hernandez.

Police believe alcohol was a factor in the shooting. There were four people in the apartment at the time of the shooting, all of whom knew each other. Three of the four people involved were off-duty U.S. Park Police officers.

“We didn’t hear anything which is good. I have a seven-month-old child and she slept through it at least is thankful for that,” said Michael Hauk, who lives on the second floor, on the other side of the building where the shooting took place.

Roy was charged with Involuntary Manslaughter and is being held at the Fairfax County Adult Detention Center on no bond.

“People like that have a lot of training[…],” said Greg Taggart, a witness. “So, you would assume that would not happen in a scenario like this.”

A spokesperson for the USPP provided DC News Now with a statement saying:

“We are aware of the incident involving off-duty United States Park Police (USPP) employees at a private residence in Fairfax County. The incident is under investigation by the Fairfax County Police Department and all questions related to this investigation will need to be referred to them. Our focus right now is on supporting the family, friends and coworkers of our employees involved in this tragic incident. USPP has nothing further to share at this time.”