The fire, which broke out at the buildings at 4:30pm on December 15, has frightened many people.
Five fire trucks have arrived on the scene while a fire apparatus was also sent there to rescue the victims.
According to a source, two first victims have been pulled out of the fire and rushed to hospital for treatment. But there were no immediate reports of their current situation.
Witnesses said many people are still trapped in the buildings.
5:30pm, the twin towers were completely engulfed in smoke. Firefighters are rushing into the two main basements of the building to attempt their rescue.
6pm, the rescue team got in touch with a group of 20 people on the top floor of the towers via cell phones. The rescuers asked the victims to gather at the northwest part of the towers so that they could rescue them safely.
The fire apparatus was sent to the west part of the buildings to rescue the victims. The rescuers broke down glass windows of the 7th and 8th of the towers in order to save trapped people.
6:10pm, the fire in basement No. 1 of the towers was put out but black smoke still covered the towers.
To Xuan Thieu, deputy head of the Hanoi Department of Fire Prevention, has arrived on the scene to direct rescue operations.
A group of Tuoi Tre reporters are now in the scene to update latest news of the fire.
6:20pm, four rescue task forces climbed to the stairs to go into the towers. The rescuers used a pulley to rescue some victims trapped inside the B tower.
Black smoke still engulfed the towers.
6:35pm, Tuoi Tre reporters at the scene confirmed that as many as 30 people in the 30th floor have been rescued. They have been taken away on the staircases.
As 6:36pm: three more fire apparatus are sent to the scene to rescue the trapped victims.
6:45pm: 7 victims brought down by fire apparatus landed safely. Four other trapped people were also safely sent to the ground by pulley but one of them sustained injuries and was taken to hospital.
6:50pm: the group of rescuers, who climbed staircases to enter the towers, said all of electric and cable wires from basements to the 30th floors have been burnt down.
7pm: The south part of the towers is still engulfed in black smoke. The rescuers are attempting to bring the water cannons to the top floor of the towers to extinguish the fire at the 30th floor to prevent the fire from spreading to other floors.
Tuoitrenews is updating
Here are some first photos of the fire by Tuoi Tre:
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