Note: I've edited the original email I received which had several factual errors in it, and reworded it a bit. I also copied some of the news text from Snopes. You can see the original email at the Snopes link below.
On Sunday December 16, 2012, 2 days after the Connecticut school shooting, a 19-year-old man named Jesus Manuel Garcia went to a restaurant in San Antonio Texas to kill his ex-girlfriend. After brandishing a gun in the restaurant, he chased multiple restaurant employees into a nearby theater. As Garcia was running through the parking lot, he shot the windshield of a San Antonio Police patrol car after an officer in the car shined a spotlight on him. The officer was not injured.
Garcia then ran inside the movie theater, where he continued his search for the restaurant employees. Movie-goers in the lobby, bathroom, and some theaters reported hearing multiple gunshots. The gunshots caused people inside the theater to panic.
"Everybody was just coming out of the side of the theater, running out the emergency exits. And everyone was screaming and running," a woman who was at the theater said.
Authorities said one person was shot by Garcia.
Garcia was finally stopped by an off-duty Bexar County Sheriff's Department officer who was working security at the theater. Officials said the officer, Sgt. Lisa Castellano, heard the gunfire inside the theater and ran towards the sound of the shooting to find out what was going on. Sgt. Castellano spotted Garcia coming out of a bathroom with his gun drawn and fired at him, shooting him four times.
Now aren’t you wondering why this isn’t a lead story in the national media along with the school shooting?
There was an off duty county deputy at the theater. SHE pulled out her gun and shot the man 4 times before he had a chance to kill anyone. So since this story makes the point that the best thing to stop a bad person with a gun is a good person with a gun, the media is treating it like it never happened.
Only the local media covered it.
On December 19, 2012 the city of San Antonio gave Sgt. Lisa Castellano a Medal of Honor for her bravery and quick thinking for stopping a dangerous man.
Sgt. Lisa Cuello Castellano was met with a standing ovation.
Bexar County Sheriff Amadeo Ortiz presented the 13-year veteran with the Medal of Valor for taking down a gunman inside a south-side movie theater.
According to police and deputies at the scene, 19-year-old Jesus Garcia ran into the Santikos Mayan Palace after firing several shots inside a nearby restaurant [and] in the parking lot.
Castellano, who was off duty, yelled for people inside the theater to get down on the ground. When Garcia came out of the restroom, Castellano ordered him to drop his weapon. When he refused, she shot him multiple times.
"I'm not going to lie; it was frightening," she said. "But, you know, the training kicks in. And thank you to the sheriff's office for all of the training that we're given."
Why didn't we hear anything about this act of valor? Snopes is on point with their assessment...I'm going to reprint it verbatim. I personally disagree that the armed guard's actions saving people are speculative. She CLEARLY saved many lives with her actions. I especially like that last line..."Reporters don't report buildings that don't burn."
In general, the San Antonio theater shooting received little coverage outside of local news media, primarily because it didn't include any of the factors that typically propel such stories from local to national news: it was not an especially horrific crime (or part of a larger crime), it did not involve any deaths or the wounding of large numbers of people, and it featured no prominent persons: it was a shooting incident in which a single person was injured. The possibility that an armed guard may have prevented additional casualties by shooting the gunman might have made the incident more newsworthy than usual, but that aspect of the story was speculative, and as others have observed , the news media tend to highlight negative events rather than positive ones: "reporters don't report buildings that don't burn."
Snopes.com : San Antonion Shooting; Media Quiet
2 Wounded in San Antonio Restaurant Shooting
And this is as close to national attention as this story received: CBSnews.com - Shots fired at San Antonio theater