A new report shows South Carolina teenager Jesse Osborn, accused of the fatal 2016 school shooting at Townville Elementary in Greenville, chose his target because no armed guards were on the school’s campus.

The Washington Post reported Saturday that the 14-year-old Osborn, hoping to outdo the casualty numbers of previous mass shooters at Columbine High, Sandy Hook Elementary, and Virginia Tech, meticulously planned his rampage on his Instagram account six days before he allegedly fired upon the Townville grade school playground.

Osborn killed one 6-year-old at the school and his own father at home before going on the rampage. Two other students and a teacher were injured in the shooting.

Osborn wrote prior to the Sept. 28, 2016 shooting a reference to Sandy Hook killer, Adam Lanza, and noted that he wanted to kill “Atleast 40.” The information was revealed during a five-day hearing that began Feb. 12.

“My plan,” Osborn wrote through misspellings, “is shooting my dad getting his keys getting in his truck, driving to the elementary school 4 mins away, once there gear up, shoot out the bottom school class room windows, enter the building, shoot the first class which will be the 2d grade, grab teachers keys so I don’t have to hasle to get through any doors.”

Two days thereafter,Osborn told his chat group on Instagram he was unsure if he should shoot up his middle school, which he had already been expelled from. Additionally, he said that the elementary school would “be like shooting fish in a barrel” because there would be no armed security there.

Osborn was tackled by a volunteer firefighter after the .40 caliber pistol the 14-year-old used jammed just seconds after he began shooting.

The judge agreed with prosecutors that Osborn should be tried as an adult because as a juvenile, he can only be held in the system until he turns 21. Osborn’s defense team, however, argued that the teenager was a bullied student who was also mistreated by his now deceased father.

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