Firefighters in Concord battled a stubborn blaze that ripped through a vacant three-story commercial building late Monday night, the Contra Costa County Fire Protection District reported. The fire, which ignited around 10:30 p.m. near Sunset Avenue and East Street, prompted a swift two-alarm response as fire crews arrived to heavy smoke and flames billowing from the structure. "Engine 6 was first on scene and immediately reported heavy smoke and flames," the district shared in a Facebook post.

The intensity of the fire soon forced firefighters to defensively fight the flames from outside, having to hastily withdraw due to interior floor collapses and extensive structural damage. Captain Chris Toler, a spokesperson for the fire district, told East Bay Times, "Several parts of the building both inside and outside of it collapsed during the fire, as did part of the roof." The firefighters knocked down the fire after about 2½ hours of intense effort.

No injuries were reported, as the building was vacant during the fire. Following the initial battle with the flames, crews remained vigilant, watching for any rekindling hot spots and commencing the clean-up operation. Several road closures were put into effect to secure the area for the ongoing operation, the East Bay Times reported.

The aftermath of the conflagration left downtown Concord grappling with disruptions. Besides the closed roads, like Clayton Road at Oakland Avenue and Park Street at Grant, the nearby BART station parking lot was temporarily inaccessible. Firefighters are expected to "be at the scene for several hours cleaning up and keeping the fire from flaring up again," according to Toler via the East Bay Times. Meanwhile, the cause of the blaze remains unknown, with Contra Costa Fire Investigators set to thoroughly conduct an investigation into its origin.