A former Gwinnett County deputy was arrested after allegedly beating a man so badly that he was in a coma for days, officials said.

Robert Christopher Matt resigned from the Gwinnett sheriff’s office in 2012 after authorities said he crashed his patrol car and was charged with DUI.

Channel 2 Action News reported that Matt is now back behind bars and charged with attacking his ex-girlfriend’s new boyfriend.

RELATED: Gwinnett deputy charged with DUI after wrecking patrol car resigns

Police said Matt broke into his ex’s house in the middle of the night Jan. 28 and beat up Michael Graham, according to the news station.

Matt was arrested last Tuesday and charged with aggravated assault, aggravated battery, burglary with intent to commit a felony, making terroristic threats and third-degree child cruelty, according to Gwinnett jail records. He is being held without bond.

He also allegedly sent text messages threatening to kill Graham, Channel 2 reported.

Graham suffered injuries to his head and face and was put into a medically induced coma, his family wrote on a GoFundMe page, which has raised more than $18,000 in less than two weeks.

They said he was “the victim of an uncalled-for cowardly act that can’t be explained for any reason, excuse or justification.”

The victim’s mother, Stephanie Graham, said he loves to work out, and would not have been able to fight back if he was less strong.

“It will be a while before we know how he's going to recover,” she told Channel 2. Family members said he has since awakened from the coma at Gwinnett Medical Center.

In other news:

The alleged assault was streamed on Facebook