Firefighters evacuate a woman after a fire broke out at the World Trade Centre in Causeway Bay on Dec 15, 2021. (PHOTO PROVIDED TO CHINA DAILY)

HONG KONG – About 150 people were trapped on the roof of Hong Kong's World Trade Centre on Wednesday after a fire broke out in the building located in the bustling Causeway Bay commercial and shopping district, police said.

Police told Reuters 13 people were taken to hospital, one of them semi-conscious. City authorities said firefighters were battling the blaze with two high-powered hoses, using ladders and breathing apparatus in the effort to rescue those trapped.

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A firefighter prepares to evacuate dozens of people who were trapped inside the World Trade Centre in Causeway Bay after a fire broke out on Dec 15, 2021. (PHOTO PROVIDED TO CHINA DAILY)

The fire broke out at 12:37 pm and was upgraded to a level 3 incident, on a scale of one to five, before being put out at 4:30 pm.

Shoppers and office workers streamed out of the building as smoke billowed from it. Police halted traffic on some major roads next to the 39-floor World Trade Centre, which is home to restaurants, offices and shops.

A firefighter evacuates people who were trapped inside the World Trade Centre in Causeway Bay after a fire broke out on Dec 15, 2021. (PHOTO PROVIDED TO CHINA DAILY)

About 100 people moved from a restaurant to the top 39th floor when the fire broke out and smoke filled the dining area, broadcaster RTHK quoted police as saying.

Media said the fire broke out in a utility room on a lower level of the shopping mall at noon before spreading to bamboo scaffolding surrounding the block.

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The cause of the fire was not immediately clear.

With Reuters inputs

A firefighter prepares to evacuate dozens of people who were trapped inside the World Trade Centre in Causeway Bay after a fire broke out on Dec 15, 2021. (PHOTO PROVIDED TO CHINA DAILY)

Bystanders take photos of the World Trade Centre in Causeway Bay after a fire broke out on Dec 15, 2021. (PHOTO PROVIDED TO CHINA DAILY