Officers were called to the 300 block of North Simpson Street just after 5:30 a.m. on Monday.
Investigators say the 30-year-old victim had been stabbed in the stomach.
The alleged murder weapon was found inside a home on the block, according to police.
The victim was discovered five or six houses south of where the knife was found.
Police say three adults and a small child were taken in for questioning.
The victim has not yet been identified.
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