The shooting happened around 12:45 a.m. inside the Burger King at E. 116th Street and Lexington Ave.
Police say the suspect entered the restaurant, took out a gun, and demanded money before shooting 19-year-old Kristal Bayron-Nieves in her torso.
She was taken to Metropolitan Hospital where she was pronounced dead.
The shooter ran away with an unknown amount of cash.
He is described as having a dark complexion and a slim build, and was last seen wearing a black mask, all black clothing, and possibly carrying a black plastic bag.
Police say he also punched a female manager in the face and pistol whipped a male customer.
Police are still searching for him.
They’re asking anyone with information to call the NYPD’s Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
Tips can also be submitted online at https://crimestoppers.nypdonline.org/, or on Twitter @NYPDTips.
Ex-Brit turned Manhattan resident since 2008.