"At first I heard fighting and then I heard her screaming," said Shawn White.
Police say 20-year-old Federico Bruno was hiding in his ex-girlfriends apartment and was waiting to attack.
Just seconds after his ex came home with their 3 month old son and a friend, police say Bruno pounced.
First allegedly stabbing his ex several times, then stabbing her friend several times when she tried to call 911.
His rage building, police say Bruno turned back to his ex ad the unthinkable.
"Preliminary indications are he may have thrown them out the third floor window with the child in her arms," said Chief Thomas Comey.
About 30 feet to the concrete below, the 21-year-old mother trying to protect her baby came crashing to the ground crushing her child beneath her.
"That wasn't the end of it... He got on a fire escape climbed down then viciously beat her again with a table he found in the rear yard," adds Comey.
The most violent end to a tremulous week where police were called several times to this apartment, but Bruno's ex didn't press charges. No order Of protection either.
Now an all out manhunt and police have a message for the suspect. "What you did was egregious. You have to answer for it and one way or another you will answer for it," adds Comey.
The 20-year-old with an extensive criminal history on the run while his son, the mother of his child and her friend all fight for their lives.
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