SAN FRANCISCO (CBS SF) — While many were celebrating a July 4th weekend without COVID-19 restrictions Saturday, anxiety was growing among fire crews, fearful that illegal firework use could ignite a major wildfire.

Cal Fire is coming off historic year of battling wildfires and 2021 is already off to a challenging start as the extreme drought conditions have turned hillsides brown with dried out vegetation.

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“Our message is simple,” said Cal Fire Assistant Director Daniel Berlant. “We have a zero tolerance for the illegal and unsafe use of fireworks.”

Berlant that even a single spark from illegal fireworks can trigger a deadly disaster.

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“We have extreme drought,” he told KPIX 5. “It is incredibly dry. And even though the 4th of July is the unofficial start of summer, we’re expecting a lot of people out in the wildland — out recreating, out celebrating the 4th of July.”

Cal Fire has teamed up with local enforcement across Northern California, cracking down on the sale of illegal fireworks. Thousands have been confiscated and safely destroyed. Arrests have been made.

“Illegal fireworks are by design a major fire risk,” Berlant said. “And that’s not to mention the safety hazards they also pose. And so, we respond to thousands of fires every year and even injuries.”

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“We’re urging all Californians to leave fireworks to the professionals,” he continued. “Go to a community fireworks show. That is your safest bet.”