A deadly blaze killed nine people and injured another 33 in Mong Kok in downtown Hong Kong on Wednesday morning.

The cause of the fire on Fa Yuen Street, a tourist destination famous for its women's commodities market, is suspicious and arson has not been ruled out, Anna Tsang, the police deputy district commander for Mong Kok district, told the Global Times.

Firefighters pulled nine charred bodies from the burned building. Police spokesperson, Siu Mo-Fun, told the Global Times they were found in the stairways. Thirty-three other people, including a one-year-old infant, were rushed to hospital. Five of them are in critical condition.

"The blaze started at around 4:40 am, and the first firemen on scene reported seeing separate fires on both ends of the hawker stalls before spreading to a block of nearby flats," Tsang said. "It took nearly eight hours and the fire was mostly extinguished by 12:30 pm."

Twelve fire engines and 12 breathing apparatus teams attended the scene. Witnesses said many residents fled to the rooftop and waited for rescue. Police cordoned off the entire block of Fa Yuen Street, and about 400 people were evacuated from the area. It was reopened around 4 pm after police had finished gathering evidence.

Hong Kong's chief executive, Donald Tsang, told a press conference at Kwong Wah Hospital he was shocked and deeply saddened by the blaze.

"It is not the first time we have seen this type of problem - last year there was a fire on the same street," Tsang said. "We have taken steps, including separating hawker stalls from residential blocks and limiting expansion of the stall areas. But it isn't enough."

The Home Affairs Department and Social Welfare Department have set up help desks to look after the needs of victims and displaced residents, including housing and immediate financial assistance.

Florence Hui, Acting Secretary for Home Affairs, told reporters the government has set up a temporary shelter for more than 70 families displaced by the fire in a community center. And the department will help people apply for financial aid.

Tsang has promised a thorough investigation into what caused the fire. Last December, some 80 stalls burned to the ground on the same street, injuring seven people. A cook was accused of starting the fire after police finished the investigation into its cause.