The blaze broke out in the basement of the CT4A Block, part of the apartment building located in the Xa La urban area in Ha Dong District, at about 7:25 pm, Tien Phong (Vanguard) newspaper quoted local residents as saying.
About 30 minutes later, while the flames were rising, locals heard some explosions and the power supply suddenly cut out, the newspaper said.
As the basement is also connected to the two other tower blocks, CT4B and CT4C, the fire and smoke also affected residents in those towers.
Rescuers use ladder trucks to search for victims of the fire at the 34-storey apartment building. Photo: Tuoi Tre
Amid the rising black smoke columns, thousands of residents rushed down from the upper floors in order to escape the building.
At the same time, hundreds of firefighters, rescuers and health workers were deployed to the scene.
Firefighters and rescuers tried to access and protect hundreds of people who were stuck on the higher levels of the high-rise.
Around 10:00 pm, firefighters got the fire under control and rescuers took all the trapped residents to safe places 45 minutes later.
Rescuers are pictured carrying victims of the fire into an ambulance. Photo: Tuoi Tre
The fire claimed no lives but injured an unknown number of people, a firefighting official said.
At 10:30 pm, two injured victims were sent to Hanoi-based Ha Dong General Hospital, while many others were taken to Hospital 103 and the National Institute of Burns in the capital.
The fire was alleged to have started in the transmitter station in the basement, where hundreds of motorbikes were parked, sources said.
Police are investigating the cause of the blaze.
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