ST. PETERS, Mo. — The deadly shooting at Maryland Heights Community center has gun owners talking about safety.

"The way it's happening today, it's just pretty brutal and saddening to see so many families heartbroken over gun violence," said gun owner Ricky Byrd.

Monday night at the Maryland Heights Community Center, the family of 45-year-old Maria Lucas were left with broken hearts after police and prosecutors said she was shot and killed by a fellow employee. 

"You wonder sometime about the background and the family structure or what they're thinking about when they get up each morning," added Byrd.

RELATED: Man charged with murder in Maryland Heights Community Center shooting

After a 20-year career as a police officer, Paul Bastean is continuing protecting others by teaching active shooter and concealed carry classes. 

"It's a very different world than what we grew up in, so you just have to be aware. We have so many people that get so distracted by cell phones and all these things that stuff happens right on top of them before they have any awareness, and that situational awareness is key," said Bastean.

It's why teaching people how to protect themselves has become his new mission. 

"Most active shooter situations are usually done withing three to five minutes and sometimes it takes a cop three to five minutes to show up, so the inherent risk that we have to accept in law enforcement is having to go in by ourselves," added Bastean.

That's exactly what police said the Maryland Heights officer did Monday. 

"He's a hero. He probably saved a lot of lives. He reacted and it was a good thing he did because a lot more people could've gotten hurt," added Byrd.

Maryland Heights city officials confirmed their employees do complete active shooter training.

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