Dallas police officer Amber Guyger was sacked after an investigation determined she "engaged in adverse conduct when she was arrested for manslaughter" in the killing of her black neighbor, officials told FOX News.
Guyger was sacked during a hearing Monday, Hall said.
In a statement released on Twitter, the department concluded that Guyger "engaged in adverse behavior" when she shot and killed Jean.
Guyger was charged with manslaughter in the killing; she is now free on $300,000 bond. "Under civil service rules, Officer Guyger has the right to appeal her discipline". Hall also argued that firing Guyger could impact the criminal investigation. The criminal investigation in the case is ongoing.
A Dallas police officer was arrested Sunday on a manslaughter warrant in the shooting of a black man at his home, Texas authorities said.
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Guyger reportedly moved out of the Southside Flats apartment complex - located just blocks away from Dallas police headquarters - last week.
When Guyger put her key in the apartment door, which was unlocked and slightly ajar (according to the affidavit), it opened. A neighbor told police that he "heard an exchange of words, immediately followed by at least two gunshots", the search warrant affidavit said.
Police said Guyger, who was dressed in full uniform, shot Jean in his apartment.
Hall, meanwhile, said at a town hall meeting on Tuesday that she couldn't fire Guyger before an internal probe was conducted, the Dallas Morning News reported.
Some of the demonstrators rolled empty coffins as they marched outside AT&T Stadium in Arlington, Texas, ahead of Sunday's Cowboys game to protest recent fatal police shootings.
This is a developing story and will be updated.