Contra Costa County fire officials say crews responded to reports of a fire burning in the 4100 block of Pacheco Blvd. around 3:45 p.m.
Crews on the ground and in the air were able to protect structures that were immediately threatened by the fire.
Thankfully, no evacuations were issued and no buildings were lost.
SKY7 was over the fire which produced a huge plume of smoke that blanketed parts of Interstate 680 which was not too far away.
Crews responding to 3-alarm brush fire burning in Martinez
Investigators determined that the fire started at or near a homeless encampment.
Stay with ABC7 News for the latest details on this developing story.
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