BROOKSVILLE ó A Hernando County court convicted George Mason III Wednesday of three 2014 murders that investigators called one of the most horrific shooting rampages in Brooksville history.Mason, 46, was found guilty by a jury of three counts of first-degree murder and one of attempted first-degree murder, court records show. He is set to appear again in court Monday, when jurors will consider the death penalty.On the night of Aug. 29, 2014, police said Mason shot four people at a small, cream-colored house at 820 Peach St. ó home to his half-brother, Gabriel "Bo" Taylor, their mother Tracy Taylor and their 81-year-old grandmother, Jannie V. Taylor.Three people died: Tarasha Yata Townsend, Masonís 37-year-old girlfriend and mother of his two daughters; his grandmother; and Ralph Peyton, another son of his motherís. Gabriel Taylor, 33, was critically wounded.At the time, police said they werenít aware of a motive. Mason was "just hellbent on a violent outrage," said Brooksville Police Chief George Turner.PREVIOUS COVERAGE: Three people killed in Brooksville shootingAfter the killings, investigators said, Mason chased Gabriel Taylor to the corner of Main Street and Martin Luther King Jr. Boulevard, where he shot him multiple times with a 9mm handgun. Then a passing pickup hit Mason, who ended up in the hospital with several broken bones before he was charged.Records show Masonís criminal history goes back to 1991. Between 1992 and 2007, he served four terms in state prison for cocaine and marijuana sales and possession, battery on a law enforcement officer, fleeing law enforcement and felon possession of a firearm, among other crimes, Florida records show.Contact Megan Reeves at [email protected] Follow @mareevs.