57-year-old Larry Brown was taken into custody after a woman told police she saw him in Harlem.
Police officials said he told them he planned to turn himself in.
According to police, Brown tied up and gagged his aunt and uncle, Mazie and Boatman Garris, inside their Harlem home Monday.
He allegedly stabbed his aunt in the head and stole some of her cash.
She's recovering at Harlem Hospital.