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"They were both struggling to gain control of the baby," Orzech said.
Denzel Castile, 19, broke away with the infant and stabbed her twice before charging at officers.
An SPD officer scooped up Athena and rushed her out to the ambulance squad that had arrived.
"They took off right away to the hospital. Lifeflight was there but they couldn't get the baby stabilized. They worked on her for several hours and she passed away," Orzech said.
A woman in the house said Castile erupted in violence.
"He started going crazy. He just blew up. He just blew up. He lost it,” a witness told police immediately after Castile, 19, broke away and stabbed Athena.