A fire broke out on September 12 at a mini apartment building on Khuong Ha Street, Thanh Xuan District.

The fire broke out at 11.50 pm on September 12 from the ground floor of a mini apartment building on Lane 29/70, Khuong Ha Street. The 200-square-metre 10-storey building houses 150 people who were mostly renters. There were five apartments of between 20-40 square metres on each floor.

Arriving at the scene on Wednesday afternoon, Dung said it was a catastrophic incident.

"We've asked the police to investigate the case and strictly fine those responsible," the official said. "We've also requested fire prevention inspections at all facilities at risk of fire, especially mini apartment buildings in the city."

According to the Hanoi party secretary, initial investigations showed that the building on Khuong Ha Street had a construction permit for six storeys. However, the investors had made it a 10-storey building with 45 apartments. The fire prevention system had also been officially checked and approved in the building but it just failed to work when the fire occurred on Tuesday night.

"Authorities in all districts have been asked to carefully check fire prevention systems at all facilities in the area and address all problems before reporting to the municipal people’s committee by October 30," he said.

Hanoi Police have detained the owner of the building for violating fire safety regulations.