The Oakton resident was outside his Waples Mill Road home when he got into " an interaction with a man that led to an altercation," county police said.
The homeowner returned to his home and got a firearm, but the other man followed him in with what police say was a large rock.
That's when the homeowner shot the invader, police said.
He was pronounced dead at the scene, and authorities have yet to share his identity.
The resident was taken to the hospital with non-life-threatening injuries, police said.
Authorities do not believe the pair were connected in any way and are investigating the incident as a self-defense shooting
Police also noted that there were two kids and two other adults inside the home at the time of the deadly incident.
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