Police say 24-year-old Tina Negro suffered a stab wound to the torso and was rushed to Beth Israel Hospital, where she later died.
They say a second woman, 27 years old, was slashed in her torso and leg. She is in stable condition at Beth Israel.
The male suspect, identified by police as James Gonzalez, reportedly fled the scene. He is described as a male Hispanic, about 5-foot-11, with short hair and wearing a green jacket.
The motive for the attack is not known, but some witnesses say the intended target was Gonzalez' girlfriend. Police have not confirmed that.
Police dogs were tracking the scent of a jacket that was left in the front of the store.