The South Coast Air Quality Management District said air quality was considered unhealthy Sunday due to Saturday night's fireworks.
Although fireworks are illegal in the city of Los Angeles and all firework displays are banned in L.A. County this year, that didn't stop residents from putting on a show for their neighborhoods.
Video captured from ABC7's stationary cameras throughout the region, including one at LAX, showed how widespread they were being set off.
Video captures widespread view of illegal fireworks across Southern California on Fourth of July
Many people said they enjoyed the fireworks displays, even though it put the public in danger.
"It sounds like they're teaming up to make sure everybody here, everybody over there, everybody in this vicinity is getting the right amount of fireworks -- no matter where they are," Sheikh Ahamed said.
The Los Angeles Fire Department said it responded to over 100 fires, including 29 structure fires, 12 brush fires and 116 rubbish fires. It's unclear if fireworks were responsible for all them but the department tweeted "Fireworks are not toys."
A brush fire erupted next to an apartment complex in Mission Hills. Meanwhile, in Covina, several trees caught fire. Investigators were trying to determine if fireworks were to blame in both incidences.
East Los Angeles was trending on Twitter as many likened the multitude of amateur firework displays to a show at Disneyland.
Marc Cesar captured an overview of what the illuminated night looked like across the city.
Illegal fireworks illuminate LA skyline; 2 fires possibly linked to 4th of July celebrations
Santa Ana and Fontana were also trending.
The Los Angeles Police Department Communications Division asked people not to call 911 to report illegal fireworks unless someone is hurt or there was a fire.
The agency tweeted that the emergency lines were being inundated with calls and asked people to instead call (877) ASK-LAPD or to report the incident online, noting that there would be delays as they sorted through nearly 800 online reports.