The rest of the story (about the security guard). This is what I gleaned from several articles:
Security guard Shamson Sandara was former Marine with combat time and a former deputy sheriff working for a company that had a security contract with the school.
The contract forbid the security guards from having weapons, but Sandara carried his personal handgun anyway.
When the perpetrators started their spree, one student was killed and several wounded. The student killed, Kendrick Castillo, along with a couple other students, rushed and tackled one of the perpetrators at the cost of Castillo's life.
Sandara disarmed and detained the other perpetrator at gunpoint, using his own gun.
Sandara scanned the area and saw a man in civilian clothes pointing a handgun around a nearby corner. Sandara fired two shots at the man, which missed him but penetrated a wall behind him and striking two students on the other side of the wall with non-life-threatening injuries . Once law enforcement officers identified themselves Sandara cooperated with them.
A DA separate from the one handling the prosecution of the perpetrators investigated Sundara' actions and decided that he committed no crime by firing his weapon because of the ongoing deadly attack. However having the handgun was illegal, and in a "consultation" with the families of the wounded students, the school district, and law enforcement (and presumably Sandara's lawyer) Sandara will not be charged with a crime, but will have a "deferred action" that requires him to complete 50 hours of community service and a few other requirements, and upon successful conclusion the "deferred action" will be "closed."
The father of student killed while attacking one of the perpetrators praised Sandara as a hero. The head of the security company that Sandara worked for also praised him as a hero and promoted him to head of recruiting for the company. (Amazing, no under-the-bussing).
Some links:
https://www.montrosepress.com/stem-scho ... edd21.html
https://denver.cbslocal.com/2020/01/24/ ... t-student/
https://www.9news.com/article/news/loca ... ed5ecbb1c5