Police were called to a home on the 7000 block of Infantry Road in Manassas around 3:30 p.m., where two people had been stabbed, county police said.
Officers opened fire, killing the knife-wielding man near the front entrance of the building, whose identity had not been released as of press time.
One of the two people stabbed by the man had died as of 7:20 p.m. The other remained critical, police said.
A knife was recovered at the scene and the identities of the deceased will be released pending notifications of their next-of-kin.
CIRT investigators have arrived on scene and will be assuming the investigation. Further updates will be released when available. The investigation continues.
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