BROOKLYN - Police say they are investigating after at least four people were killed in three separate Brooklyn shootings.

Authorities say three people were shot yesterday morning at the Sheepshead-Nostrand Houses in Sheepshead Bay. They say two of the victims were killed, while the third is in critical condition at Kings County Hospital.

According to police, just three hours before the triple shooting, 24-year-old Calvin Louis-Juste was shot near his home on Moffat Street in Bushwick. Louis-Juste, who had just obtained a Master's degree, was pronounced dead upon arrival at Wyckoff Hospital.

Officials say the third shooting happened early this morning in Crown Heights when 37-year-old Karreem Russell was shot in the head and arm while riding his bike along Pacific Street.

Official say no arrests have been made. Anyone with information is urged to call Crime Stoppers at 1-800-577-TIPS.

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