This story has been updated to state that the freeways are now open and the fire has been put out.

The fire at the Wood Street encampment is sending a plume of smoke over the San Francisco Bay and downtown Oakland. (KRON4 News)

OAKLAND (KRON) – A two-alarm fire in an Oakland homeless encampment involving multiple has been extinguished and all lanes on the nearby freeway connectors are reopened after being closed earlier. The fire broke out near the entrance to the Oakland-San Francisco side of the Bay Bridge under the MacArthur maze, according to a tweet from the Oakland Firefighters union Monday.

The fire was at 34th and Wood Streets, near where Interstates 80 and 580 meet. All lanes were blocked on northbound 880 at Interstate 80, but have since reopened. Oakland Fire Engine 3 responded and requested another engine’s assistance.

At least 20 cars and several RVs that were parked under the freeway were engulfed in the blaze. Heavy smoke blocked nearby freeways and the westbound I-80 to southbound I-880 were shut down with motorists diverted to the Bay Bridge toll plaza. The eastbound I-580 was also shut down, according to the CHP.

“Multiple cars, debris and RVs are burning,” according to a tweet from the Oakland Fire Department, which contained video.

No injuries have been reported, according to the Oakland Fire Department.

According to Oakland Fire Chief Reginald Freeman, the fire was reported at around 10:20 a.m. and the second alarm was struck about 20 minutes later.

“We have a little bit of everything burning,” Freeman said. “We have cars, we have RVs, we have a ton of combustible materials — hazardous materials. We had several explosions.”

When asked to elaborate about the hazardous materials, Freeman said they included “everything from propane to other pressurized cylinders to acetylene cylinders.”

Capitol Corridor Amtrak train 531 is stopped in Emeryville due to the emergency response, according to a tweet from Amtrak.

This is the latest of several recent fires at the Wood Street encampment, several of which have sent flames into close proximity with the infrastructure of the nearby interstate.

“We’ve had numerous fires here at this location,” Chief Freeman said. “And every time, we have concerns about the structural integrity of the interstate.”

Freeman said the structural system of the nearby interstate would “have to be looked at to make sure that the structural integrity’s not compromised.”

The Emeryville Police Department also tweeted about the fire, which is near the border between Oakland and Emeryville.

Oakland Fire Chief Reginald Freeman stated in a Twitter video that the fire is “still a very active incident with approximately 65 firefighters on scene,” as well as mutual aid from the Alameda city and county fire departments.

Signs posted to the are with the date of July 7 ordered residents to vacate the encampment, saying “the public works department has deemed this site uninhabitable” and ordered residents to “vacate this site and remove any personal belongings.

According to the posting, the public works department was scheduled to begin clearing and closing the site on Monday. Video shot in the area Monday showed what appeared to be public works vehicles clearing out cars and other debris from the area.

The cause of the fire remains under investigation.

Bay City News contributed to this report.