Authorities say the boy, Adiel Rosario, was with his parents from a sixth-floor bedroom just before 12:15 a.m.
One of the shells struck the window and exploded, causing a laceration to the boy's left bicep that required stitches.
"He got burned all over his arm, and they gave him at least five stitches," dad David Rosario said. "I took him to the hospital myself...(My kids) were crying all night, until we got back from the hospital."
He also suffered first- and second-degree burns.
Anyone with information pertaining to this incident is asked to call NYPD's Crime Stoppers Hotline at 1-800-577-TIPS.
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