12:50 PM PT -- The Broward Sheriff's Office has also fired Peterson for neglecting his duties at the high school on the day of the shooting after an internal investigation.

The Broward County Sheriff's Deputy who fled at Marjory Stoneman Douglas High School when a mass shooting broke out has been arrested for failing to do his job and help limit the carnage ... and he's facing up to 96 years in prison.

Scot Peterson has been arrested and charged in Florida and has been hit with 11 criminal charges stemming from the Parkland shooting on February 14, 2018.

The charges include 7 counts of child neglect, 3 counts of culpable negligence and one count of perjury. This comes after a 14-month investigation where law enforcement interviewed 184 witnesses and reviewed countless hours of surveillance footage.

Peterson's bond has been set at $102k ... but if he posts it he'll be required to wear a GPS monitor, turn in his passport and forfeit any firearms he has.

As we reported ... Peterson was tasked to guard the school, but video shows him running away from danger when 19-year-old gunman Nikolas Cruz opened fire on the school.

He's also been sued by families of the victims.