ANTIOCH (KPIX) — On the precipice of the July 4th weekend, Contra Costa County firefighters sent out one last warning about the dangers of fireworks, and they set a set a hillside on fire to make their point.

“The point of the demonstration is that even with ‘safe and sane,’ in approximately a minute, the fire can get out-of-control,” said Contra Costa County Fire Marshal Chris Bachman. “It’s probably leaving your yard, getting into your neighbors yard, getting into open space, putting other structures and people in danger.”

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Just a single sparkler in grass this dry and this is what happens in a matter of seconds. It’s exactly what Contra Costa County Fire knows is coming over the next several days. They have seen it before.

“Last year, on the fourth, in a three hour period, we responded to almost 100 fires,” says Steve Hill of County Fire. “Pretty much unprecedented. That’s about a month’s worth of fires in three hours.”

Just this past memorial day an apartment building in Antioch was destroyed by a fire, started by fireworks. People across the area have their own stories of close calls.

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“One of their neighbors was lighting off fireworks and burned down the entire fence, a tree, and half their backyard,” says Peter Vickrey of Antioch. “So, it’s a concern.”

“In these conditions, we talked about the drought a moment ago,” Hill says. “With the wind, every single day is windy.”

The department will be fully staffed this weekend with an additional 50 personnel and 8 trucks on hand. But they’re warning everyone; extra staffing does not guarantee help will be there in time if disaster starts to unfold.

“Remember, it’s a very busy evening for us,” Bachman says. “We are stretched thin if residents set off fireworks anyways and they start a bunch of fires.”

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Fire officials in Contra Costa County have launched a new hot line for people to report the use of pyrotechnics. Any residents who see or hear illegal fireworks over the holiday weekend can call 1-833-855-2021 to report it to authorities.