Sometime before 4:15 p.m. on August 23, a man was stabbed in the stomach while waiting on a platform, NBC4 Washington reported.
The victim was found unconscious and not breathing, the website said.
A woman was also cut in the incident and was taken to a local hospital to be treated for non-life threatening injuries, NBC4 Washington said.
Detectives were on the look out for a black male wearing black shoes, a dark blue short sleeve shirt, blue jeans, and carrying a green bag, police reported.
Anyone with information should contact D.C. police.
Click here for the full story from NBC4 Washington.
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