By CBSLA Staff

ONTARIO (CBSLA) — It was just about lunchtime on a sunny Tuesday in March when Arlene Fierro started recording a series of fireworks exploding in her neighbor’s backyard.

“We have heard those sounds before,” she said. “So that was, I guess, the scarier part. We didn’t really expect it at all, because it was something that happened on the daily.”

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Within minutes, as she ran inside to check on her family, came the massive and deadly bomb-like blast. Her family made it out OK, but Fierro’s mom is still traumatized by what they went through.

“I’m outside and my daughter’s in danger inside,” she said about the blast through tears.

Two men at the home were killed by what authorities said was a huge stash of illegal fireworks that they were possibly selling.

SEE MORE FROM THE MARCH 16 BLAST

Following the explosion, residents said they had reported the use of illegal fireworks to police numerous times. According to records kept by the Ontario Police Department, officers had responded to 50 illegal fireworks calls within a one block radius of the home in the past year — about one call per week — but nothing changed.

The Fierro family said they too had tried to report the activity before.

“I remember being pretty specific, saying, ‘My neighbor’s next door are doing illegal fireworks,'” Fierro said.

Just weeks after the blast, San Bernardino County Fire Department officials launched a new tool to help crack down on the use and sale of illegal fireworks, and the public reporting and mapping system has tips coming in by the minute.

The map shows where the most reporting activity has taken place over the last few weeks. Fire Marshal Mike Horton said the department then uses that information to help pinpoint where to send investigators.

HEAR MORE FROM FIRE MARSHAL MIKE HORTON

“We can deploy resources out and be more effective in the field and try to reduce the problem of fireworks in our county,” Horton said.

Fire officials said the popularity and profitability of illegal fireworks means an explosion like the one that rocked the Ontario neighborhood could easily happen again.

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“It’s being sold out of residences, out of commercial properties, out of storage units,” Horton said. “It’s being advertised on social media.”

One report that came into the new system had a photo of someone selling illegal fireworks online. Over the past year, tons of illegal fireworks were seized in San Bernardino County — either purchased out of state, south of the border or even through ports like Long Beach.

“And that’s just the tip of the iceberg,” Horton said.

He said the illegal firework trade can even have a larger profit margin these days than drugs.

“We see the discounts that people are getting on these fireworks,” Horton said. “Buy three boxes for the price of one.”

Horton said dealers then bring those fireworks back into the county and sell them online with an at least 100% profit margin — turning hundreds of dollars into thousands through illegal sales.

Mike Tockstein, with Pyrotechnic Innovations, said people can easily forget the dangers as they put on a show.

“You could be wearing the wrong clothing and cause an [electrostatic discharge] spark,” he said.

HEAR MORE FROM FIREWORKS PROFESSIONAL MIKE TOCKSTEIN

Over the past four years, San Bernardino County has confiscated more than 121,600 pounds of dangerous and illegal fireworks — enough to fill about three large semi-trucks — and issued more than 700 citations, but the sale and use of illegal fireworks continues to climb.

Fire investigators said they hope the new reporting system can help prevent another tragedy.

“It just makes me think that there’s little ticking time bombs in every city,” Fierro said. “It’s not going to really change unless people are reporting it, taking the picture and stuff, that’s the only helpful thing that I can think of, but it’s scary knowing that they’re out there.”

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The U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives as well as counties like Los Angeles and cities like Anaheim and Compton have all expressed interest in using the fireworks mapping system being used in San Bernardino County to curb the local sale and use of illegal fireworks.