Police say the 43-year-old woman was stabbed inside a home on 56th Street in Maspeth just before 6 a.m., allegedly by her ex-boyfriend.
She suffered wounds to the neck and was rushed to Wyckoff Hospital.
Her 22-year-old stepson was stabbed in the back outside the home. He went to Elmhurst Hospital, and his injuries were not considered life threatening.
The woman, who neighbors said was well-liked, was listed in critical condition.
Detectives believe the suspect, a 33 year old man, jumped in front of an LIRR train in Queens immediately following the stabbings.
One man was fatally struck by the LIRR train at 8:33 a.m. this morning near the Fresh Pond freight yard, just blocks from the crime scene.
The body was badly mangled and the medical examiner will have to make a positive identification.
Nobody on the train was injured.
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