INDIANAPOLIS (WISH) — The head of the FBI office in Indianapolis is highlighting the importance of reporting anything and everything. It’s a response to the mass shootings in El Paso and Dayton.

Special Agent in Charge Grant Mendenhall says they are working around the clock to find, and stop, threats of mass shootings. But he also says there’s only so much they can do and that they need everyone to step up to prevent a potential tragedy.

We fear the sound of gunfire, but it’s a sound that has become all too common.

“Not if, but when,” Mendenhall said. “We have to be prepared everyday.”

Within 24 hours, there was a shooting in El Paso, Texas and Dayton, Ohio. Some are wondering what’s next?

“I wake up everyday thinking about exactly what we’re talking about,” Mendenhall said. “With our shop here, I take the view that we have to be prepared everyday. We have to stay ahead of those threats. We don’t talk about responding. We talk about preventing.”

The closest incident was last year in Hamilton County when a teacher and student were shot.

“I think the day we don’t expect it to happen is the day that it’s going to happen here,” Mendenhall said. “We have the example from Noblesville Middle School, which really brought it home to the state of Indiana that these events can happen right here at home.”

The FBI uses the term “home grown violent extremists.”

“In many cases working by themselves, becoming radicalized and sometimes communicating with people overseas on how to do things,” Mendenhall said.

There are 56 FBI offices across the state. Every single office is currently investigating threats of mass shootings. Mendenhall says so far this year they’ve investigated hundreds of threats. But not all of those have been threats to life. Sometimes it takes one FBI agent or an entire squad to investigate one threat.

“There’s almost always someone who knows,” Mendenhall said. “They may not know the event is going to happen but they may have seen a behavioral change in the individual.”

54-percent of people don’t report something they find suspicious. Now, more than ever, the FBI says they rely on people.

“As a country, our citizens are becoming more aware of the threat,” Mendenhall said.

The FBI says it’s harder for them to track one person than a group, especially someone who isn’t online and may be sitting in a basement planning an attack.

“It’s harder to find an investigative tool that can get us there,” Mendenhall said.

Over the weekend, three people were arrested in three different states who may have been planning mass shootings.

Can lone actors be stopped?

“Some people would say that we can’t stop them all,” Mendenhall said. “We don’t buy that. Our objective is to stop every single one.”

A reality that we need to be vigilant more than ever.