A student has a gun and is shooting at classmates.
This scene plays out on a large screen in Brownsville.
In front of the screen Jaime Escobedo shoots an unarmed gun, connected to a receiver.
Escobedo is president of American Firing Range and American Surveillance Company in Brownsville.
He uses the technology to train local police to respond to situations similar to what Brownsville Police faced Wednesday.
Police said 15-year-old Jaime Gonzalez had a gun inside Cummings Middle School.
According to the Brownsville school district, two unarmed security officers were on scene.
Only after Brownsville Police arrived was the gunman taken out.
Police said they had no choice but to shoot Gonzalez.
Gonzalez later died.
Escobedo said he believes teachers and school staff should be allowed to carry firearms.
"I definitely think that firearms would have provided an additional deterrent for the child, for the 15-year-old boy that brought the firearm to school, said Escobedo.
But guns on school campuses brings many opponents.
A concern is that with more guns on campus could come more accidents.
That's where Escobedo said training is key.
"I do believe teachers have a right to be armed| as long as they're trained and licensed, said Escobedo.
A federal law only allows law enforcement to carry weapons on a school campus.
The Brownsville school district said armed school district police officers are always present at their high schools.
Middle and elementary schools, however, reportedly have the constant presence of unarmed security guards.