The stabbing happened Friday inside an apartment building on Rochambeau Avenue just after 10 p.m.
Authorities say a couple was visiting a 33-year-old woman when the suspect approached them and may have inappropriately touched one of the women.
The 45-year-old man stuck up for his girlfriend before the man pulled out a knife and stabbed the 29-year-old woman and her boyfriend, police said
They both died of their injuries.
The 33-year-old was cut on the hand.
The identities of the victims have not yet been released.
The attacker got away on a motorcycle. So far no arrests have been made.
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