Steve Taehee Ha, 43, was arrested by officers quickly after gunning down 31-year-old Reston resident Hyung Joon Choi inside the gym, according to officials.
Police say that Choi suffered a gunshot wound to his upper body, was rushed to an area hospital with traumatic injuries, where he was pronounced dead.
The incident was reported at around 1:15 p.m. on Tuesday, Aug. 20. He was in custody less than eight hours later.
Ha was charged with second-degree murder and use of a firearm in the commission of a felony. He was taken to the Fairfax County Adult Detention Center, where he's being held without bond.
The shooting remains under investigation.
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