An “apocalyptic” blaze engulfed a building near Central station in Sydney on Thursday afternoon, sending a massive plume of smoke into the air and causing parts of the building to collapse. More than 100 firefighters worked to contain the massive fire. Fire and Rescue NSW said it would be a “substantial and very prolonged” effort to extinguish the blaze completely. NSW Fire and Rescue’s deputy commissioner for field operations, Jeremy Fewtrell, said Thursday evening, adding that the fire had been “effectively contained” by a combination of aerial and ground work, although he added: “I expect that we’ll be here all night and into the morning.” An onlooker described seeing parts of the burning building falling onto the footpath. The fire also disrupted commuters, causing roads to be closed and light rail services to be stalled. Sign up for Guardian Australia’s free morning and afternoon email newsletters for your daily news roundup Fire and Rescue said they received multiple triple zero calls just after 4pm when flames started engulfing a seven-storey building at Randle Street in Surry Hills. Parts of the building have collapsed, and flames spread to nearby residential apartments. “It was essentially a candlestick,” a resident who lives about 100 metres from the blaze told Guardian Australia. “It was basically apocalyptic, there was ash falling everywhere, the embers were raining down.” The resident was working from home and smelled smoke shortly after 4pm. He heard “cracks and bangs” as the wall of the building collapsed, and the fire radiated heat through the surrounding streets. “It still smells acrid,” he said more than an hour and a half after the blaze began. At a press conference on Thursday, Fewtrell said there was no indication of any injuries to any of the members of the public, and no indication anyone was in the building at the time of the blaze. “That’s obviously a prime concern when our crews arrived,” he said. “The information we have [is that the] buildings were vacant or unoccupied … they were under construction or about to have to demolition or work done.” One firefighter sustained a small minor burn to his arm, and is receiving treatment from NSW ambulance paramedics. The injury does not require major treatment. At least one vehicle in the vicinity was destroyed by fire, Fire and Rescue NSW said in a statement. Fewtrell said he had seen fires of similar sizes, but what was significant about this one was how quickly it developed, and how many other buildings were in a close proximity to the blaze. “The risk of further fire spread is a real concern [and] our firefighters have worked very hard to stop that.” “There were some fires in there that spread into the apartment buildings, and firefighters were able to extinguish those, preventing them from penetrating further into the buildings and causing significant damage there.” Black smoke could be seen billowing from the building on Thursday, and large flames could be seen from streets away. Sirens and fire alarms were heard going off in the area. The top floors appeared to be mostly burnt through. Metal beams inside the building were seen burning red hot, and it appeared as if huge steel beams in the building had collapsed. NSW police said earlier on Thursday that evacuations and road closures were in place around Central station. Fire and Rescue NSW asked people to avoid the area. Light rail services were not running between Moore Park and Circular Quay on the L2 and L3 lines. The NSW transport minister, Jo Haylen, said buses were being rerouted. Trains at Central station were running. The building is directly adjacent to apartment blocks and backs onto a narrow lane, so the apartments and nearby offices and businesses were evacuated. Two buildings away, students sitting a final exam at Sydney Dental hospital were evacuated at about 4.15pm. Dental student Victor Choh was on the fifth floor with 30 other students, and evacuated in such a hurry that he was still wearing his loupes – specialist dental magnifying lenses – over his glasses. He and fellow students stood by on Chalmers Street for the next hour as they watched smoke billow out of the building. “We just heard about the smoke and flames and knew we had to get out of the building, and the alarm rang out as we were in the emergency stairs,” the 22-year-old told Guardian Australia. Choh and his classmates left possessions behind, including phones and keys. They were told they might be able to re-enter their building by 11pm. NSW Fire and Rescue’s Fewtrell said once the fire was extinguished, an examination into the fire would be conducted.