A UCLA professor was gunned down in a small office by a former PhD student who then took his own life yesterday, triggering cries of an “active shooter” on campus and a mad panic to effect a lockdown in a school where classroom doors can’t be locked.

Investigators in Los Angeles are still searching for a motive in Wednesday’s murder-suicide at the UCLA campus.

Sources identify the gunman as Mainak Sarkar. He used a 9mm semi-automatic pistol to kill 39-year-old engineering professor William Scott Klug in an office, before taking his own life.

UCLA officials are also reviewing safety protocols as the shooting revealed a problem with the doors on campus, reports CBS News correspondent Carter Evans.

Students in the midst of finals week filed out of classrooms and buildings with their hands raised.

“Then there was a police officer and he was like yelling at us to get out, get out, with a machine gun,” said a witness.

One student posted images of police inside the building, going door to door with guns drawn.

Students and staff were instructed to find a secure place as hundreds of LAPD officers, the FBI and the ATF responded to the 30,000-student campus. But without proper locks, students were forced to improvise, using chairs, power chords and a foosball table to make sure no one could enter.

The efforts of these panicked students attempting to improvise crude barricades and tie doors shut that won’t lock vividly illustrates the real world defenselessness of a so-called “gun-free” campus.

Here in reality, where political posturing, paranoia, and ignorance are set aside to look at data, we know that “gun free zones” are a complete and utter failure. Those twisted souls intent on carrying out personal vendettas, mass killings, sexual assaults, or robbery simply walk past plastic placards and paper policies to use the weapons at their disposal against those they have every right to assume are defenseless against them.

How many Columbines, Sandy Hooks, and Virginia Techs is it going to take before people clue into the proven fact that the only thing that stops a murderer on campus is someone else with a weapon to shut them down?

Researchers at the Purdue University Homeland Security Institute have determined that for every 20 seconds wasted waiting for a first responder, another person is shot in a typical school shooting.

They’ve also developed simulation modeling technology after studying dozens of mass shootings to determine the only effective solutions.

The simulation technology allows him to adjust police response time, concealed carry probability, and whether or not security guards are present during a shooting. He said all of these variables are something every venue should consider.

“We want you to use our model to determine what solution is best for you,” said Kirby.

He said overall, the simulations concluded if more innocent people were armed, less casualties would occur. Same goes with more security guards and faster police response times.

Other researchers at the Homeland Security Institute have come to similar conclusions born out in real-world events. They’ve concluded that the best way to defend a campus against a would-be mass killer is a combination of armed security (campus police or school resource officers) on the site, combined with concealed carriers. The concealed carriers at high school and elementary schools would be from the faculty, staff, and educators. At colleges and universities, they would include adult students with concealed carry permits.

The role of campus police in such a scenario is to close with and neutralize the threat. The goal of armed faculty, staff, and students is a simple one: turn off the lights, lock the classroom door, and ambush any active shooter attempting to gain entry in what military and law enforcement calls “the fatal funnel.” It does not take a great deal of training for a concealed carrier to aim in on a fixed location and put accurate aimed fire on anyone attempting to breach that locked door. The combination of armed on-campus responders and concealed carriers waiting in ambush puts would-be mass school shooters in a situation where they cannot effectively carry out their plans, and indeed, may prevent attempted shootings entirely.

The resistance to this model—which has been proven with thwarted real life attempted mass shootings at Arapahoe High School and Reynolds High School—is based on the personal political beliefs of administrators and faculty.

Counter-terrorism experts, security experts, and school security researchers have reached the consensus belief, supported by scenario modeling and real world events, that the fastest and most effective way to stop a mass school shooting event is to ensure that the school’s attacker faces armed resistance.

96.2 of mass shootings take place in “gun free zones” such as educational campuses.

Why are school administrators unwilling to make their campuses safe and allow their faculty and students to protect themselves?

Don’t student lives matter?