Fireworks sparked 120-acre grass fire that burned close to homes in Pittsburg, fire officials say

PITTSBURG, Calif. -- Investigators are looking for whoever's responsible for setting off fireworks that caused a four-alarm Pittsburg grass fire on June 17 that forced 2,200 residents to evacuate while threatening 100 homes.

The Contra Costa County Fire Protection District said Wednesday that investigators determined it was fireworks that started the early morning fire in the open space south of Jacqueline Drive.

First reported at 2 a.m., the blaze prompted a four-alarm response from both Con Fire and Cal Fire, with more than 100 firefighters and support personnel dispatched to the scene. Structure protection crews were required to protect numerous homes.

RELATED: Evacuation order lifted after 120-acre grass fire burned close to homes in Pittsburg

The fire burned 121 acres by the time firefighters knocked it down at 6 a.m. Officials said winds up to 30 miles per hour, along with extremely dry vegetation, quickly fed the fire. No injuries were reported.

Con Fire officials said the mandatory evacuation executed by Pittsburg Police and the Contra Costa Sheriff's Office, was Con Fire's first significant use of the new Zonehaven digital evacuation tool (county residents can find out more by going to www.cwsalerts.com and clicking on the "Know Your Zone" tab at the top of the page).

Con Fire stresses the danger of fireworks and the value of homeowners preparing their properties with weed abatement and defensible space creation.

The video above is from a previous report.

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