SAN FRANCISCO -- Firefighters were gaining ground Tuesday night on a six-alarm fire in the Mission Bay district.
The fire broke out this afternoon at an apartment complex under construction near 4th Street and China Basin.
San Francisco Fire Chief Joanne Hayes-White said her team was "getting the upper hand."
No injuries were reported, according to CBS San Francisco.
The cause was unknown.
Fear of buidling collapse (6:03 p.m.)
Witnesses told NBC Channel 3 News that there was concerns that parts of the building on fire could collapse. Residents in the area near AT&T Park said they were being told they could not return to their homes. NBC said the fire had been increased to a sixth alarm.
Flames 40 feet into air (6:15 p.m.)
The Chronicle said flames from the fire shot 40 feet into the air.
Smoke blowing into neighborhoods (6:20 p.m.)
Smoke from the fire was blowing to the south. There was some concerns about hot embers flying. But there were no reports that the embers had caused other buildings to catch fire.
Part of building collapses (6:30 p.m.)
Several TV news videos show part of the burning building collapsing.
Traffic snarled, area evacuated (6:45 p.m.)
The fire is a couple of blocks from AT&T Park and includes office buildings, residential units and biotech. The call on the fire came just before 5 p.m. About 100 residents have been evacuated from a nearby residential building.
The burning construction site is a massive condo development that was supposed to be finished in a couple of years.
The fire is snarling commute traffic, blocking streets that lead to freeways. Residents say the heat of the fire can be felt a block away.
Firefighters making progress (7:01 p.m.)
Firefighters have made significant progress. No injuries have been reported.
Fire slowing getting contained (7:10 p.m.)
Video from KPIX-TV shows some flames still burning but large parts of the fire out. The amount of smoke has also lessened considerably. Many evacutions remain in place.
Updated at 7:20 p.m.
Firefighters tell KCBS they are getting "the upper hand" but containment is still hours away.
"We're getting the upper hand, but we're not quite contained. We'll be here another few hours at least." http://t.co/oWVrSem8ai— KCBS 740 AM/106.9 FM (@KCBSNews) March 12, 2014
Firefighters in 'defensive mode' (7:40 p.m.)
The fire was nearly 60% contained by 7 p.m. Tuesday and firefighters were "getting the upper hand," Hayes-White said.
Hayes-White said 140 firefighters were spraying nearby buildings to prevent the blaze from burning other structures. She said there were no injuries.
"We are in a defensive mode," Hayes-White said.
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