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THE BRONX, N.Y. (PIX11) --- A 19-year-old man is accused of beating his girlfriend's 1-year-old daughter to death after slapping her on the side of the head in a Bronx apartment in August, authorities said.

Jerome Thomas has been charged with murder and manslaughter after allegedly killing 1-year-old Imani Mitchell on Aug. 29, according to court records.

Thomas was arrested the following day and charged with assault before the charges were upgraded when the baby girl died on Sept. 5, police said. The case was then ruled a homicide.

Thomas told investigators he hit the child “with a heavy hand” twice on the side of the head after the mom left the girl in his care for about 45 minutes in the Union Avenue apartment, according to

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