HONG KONG and LONDON — Scores of people were trapped in a Hong Kong skyscraper on Wednesday after a major fire broke out, authorities said.

Flames ignited at the World Trade Centre in Hong Kong’s bustling Causeway Bay shopping district at around noon local time, setting scaffolding ablaze and forcing many people inside to flee to higher floors, where they awaited rescue, authorities said.

At least 13 people were injured, mostly due to smoke inhalation, during the incident. One of the people suffering from smoke inhalation was hospitalized in serious condition, according to authorities.

Authorities said they believe the blaze emerged from electrical cables on the first or second level of a shopping mall inside the 38-story complex, which is under renovation. The Hong Kong Fire Services Department had received a notice that the World Trade Centre’s fire safety system, including alarms and sprinklers, were shut off due to the construction, authorities said.

More than 150 firefighters were deployed to the scene, according to authorities. Thick smoke was seen billowing out from the building’s entrance as firefighters used a crane to rescue people trapped on the rooftop.

By 4:30 p.m. local time, firefighters had extinguished the flames and evacuated everyone from the building. Some 770 people were evacuated by rescuers, while 40 others evacuated from the building themselves, authorities said.

The World Trade Centre complex houses offices, restaurants and a mall, but the shops were all closed due to the ongoing renovations.