Four off-duty Mesa police officers and their spouses attended the country music festival in Las Vegas on Sunday night where dozens were killed and hundreds more were injured.

Sergeant Diana Williams, spokeswoman for the Mesa Police Department, said the officers’ experience took over as they set up a trauma area to render aid to those who needed it.

However, an active-shooter event of this magnitude is something that requires more training and adequate resources.

“It’s important that we’re constantly growing, that we’re constantly learning. And, with that, we make sure that resources that are needed for these types of events are in place,” Williams said. “We have to go through what lessons were learned. So, I can imagine having training seminars on all levels from executive, all the way down on how we’re going to respond to these types of situations. It’s hard to say how we’re going to do it, but I can say we’re very proactive.”

Williams confirmed that one of the Mesa police officers was injured slightly during the shooting, but she did not elaborate on the extent of that injury.