The inferno was burning at a structure on Lester Avenue, near Lake Merritt, in a densely populated residential area.
The building had been under construction and no one was living in the building, fire officials confirmed.
There are no immediate reports of injuries.
The cause of the fire was unknown.
Oakland firefighters say they will be at the scene of this huge fire all day watching for hot spots. pic.twitter.com/h5hoZfvZfn
— Amy Hollyfield (@amyhollyfield) October 31, 2016
You can see the collapse: #Oakland #fire near #LakeMerritt. Fire chief: this is a 40-50 unit complex, no injuries, still fighting the flames pic.twitter.com/EOiPZRJ0j9
— Natasha Zouves ABC7 (@NatashaABC7) October 31, 2016
There's a big fire in Oakland near Lake Merritt. This is insane. pic.twitter.com/hd0qsZeSjk
— Dave Guarino (@allafarce) October 31, 2016
Oakland residents gathered on Lester Ave. to watch a building burn - an apartment bldg. that was under construction. pic.twitter.com/M0fKofDm8C
— Amy Hollyfield (@amyhollyfield) October 31, 2016