A Florida man allegedly admitted to police that he punched a 7-week-old girl in the head after growing frustrated while changing her diaper and was charged Monday with first-degree murder, Fox 13 Tampa reported.

Artem Eydelman, 29, was home alone with the girl, Gwendolyn Eydelman, on Nov. 17, when the alleged incident occurred. Authorities in Largo were called to the house after reports of an unresponsive child. Her biological mother was at work. Eydelman reportedly starting dating the mom while she was pregnant.

The emergency crew worked to stabilize Gwendolyn at the home and rushed her to a nearby hospital where she was placed on life support. Eydelman reportedly told police that he found the girl unresponsive. It was unclear who called 911.

Gwendolyn was removed from life support and died two days later.

Eydelman later allegedly admitted to punching the girl in the head and shaking her out of frustration while changing her diaper. The girl suffered a severe skull fracture and several fractured ribs.

He was charged with first-degree murder on Monday.

The Tampa Bay Times reported that he also faces two counts of violating his probation on charges of robbery and dealing stolen property.