The startling discoveries were made inside an apartment building on 674 East 136th Street in Mott Haven at 8 a.m.
The body of Jonathan Rivera, 38, was discovered in the hallway covered in blood with several stab wounds. From there, officers say Hanoi Peralta, 33, and Kayden Rivera, 5, were found dead inside a first-floor apartment in the same building.
Dahan Ali owns a deli in the building and knows all the victims.
"I would always see her every morning at 7, 7:30 when I came she would take her son to school, with her son every morning," Ali said.
People living in the building say the family kept to themselves and that they never saw any problems between the couple or their little boy.
"Lovely boy, very lovely -- saw home day before yesterday, he took a cookie, I said 'where is your father?' He said outside," Ali adds.
The medical examiner will determine the cause of death.
The investigation is ongoing.
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