A shelter-in-place warning has been lifted after a four-alarm warehouse fire in San Francisco Friday afternoon
Firefighters late Friday remained on scene to continue an investigation at the warehouse at 1300 Donner Avenue in the city's Bayview neighborhood.
No one was injured or displaced, firefighters said, although the flames and smoke forced the fire department to upgrade quickly from one to two, three and then four alarms by 2:20 p.m.
Firefighters struggled to get into the warehouse because its doors have been reinforced due to multiple break-ins over the years.
The public was urged to avoid the area due to the presence of "many hazards associated to this fire," officials wrote on Twitter.
People located one block north, south and west as well as four blocks east of the burning structure were told to shelter in place. Neighbors were asked to close windows and stay indoors to reduce exposure to smoke that was pouring out of the charred warehouse. The shelter-in-place order was lifted around 5:30 p.m. by which time the flames had been contained.
One level of the warehouse is on the verge of collapsing so crews are being careful about entering the building, said officials, who called the fourth alarm because they anticipate being at the scene of the fire for a while.
Witnesses told NBC Bay Area that they heard what sounded like an explosion, followed by people in nearby warehouses yelling, "Run! There's a fire!"
The fire department deployed 122 firefighters and 40 apparatuses to the scene to ensure that the flames did not spread to nearby buildings.