Authorities say the man who killed a 6-year-old boy and left a 7-year-old girl with serious injuries after stabbing them in a Brooklyn housing project elevator on Sunday night is also a suspect in the Friday night slaying of a teenager. 

NBC New York reports that the NYPD believes the same man responsible for the brutal Boulevard Houses attack that left Prince Joshua Avitto dead and Mikayla Capers hospitalized may have been carried out by whoever fatally stabbed Tanaya Grant-Copeland, 18, in East New York on Friday night.  

Grant-Copeland was discovered unconscious on the sidewalk by a taxi driver around 10:30 p.m. She was rushed to Brookdale Hospital, but ultimately pronounced dead, the victim of multiple stab wounds. According to the New York Times, the similarities between the attacksthe use of kitchen knives and the fact that they happened in such close proximity—have given police reason to make the connection.

NYPD Commissioner Bill Bratton said that police were analyzing "grainy video" of Grant-Copeland's murder, but noted that there were no security cameras in the Boulevard Houses. Mayor Bill de Blasio said there is a "massive effort" currently underway to locate the suspect.

The Times notes that police released a sketch of the assailant, describing him as "a black man about 25 to 35 years old and six feet tall with a heavy build," who was wearing a grey sweatshirt.  

According to NBC New York, the attack left Caperswho her family says is currently battling for her lifewith a collapsed lung.

[via NBC New York and New York Times]

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