HONG KONG – Hong Kong firefighters on Friday battled a blaze at a warehouse in the city’s bustling Kowloon district for five hours before putting it out, with 3,600 people evacuated from nearby buildings, although there were no reports of fatalities yet.

Yellow smoke could be seen billowing from its windows. The authorities in the Asian financial hub upgraded the fire to Level 3 from Level 1 at 2pm, on a scale where Level 5 is the highest, followed by a disaster alert.

Six people were injured, including two workers at the warehouse who were rescued by firefighters. One of them sustained burns to his hands, while the other suffered from smoke inhalation, reported The Standard.

The other four were two firefighters, a student from a nearby school and a park employee who fell ill after inhaling smoke. All were taken to hospitals nearby. 

A source told the South China Morning Post that the building had been emptied and there were 10 workers carrying out demolition work on the second floor when the fire broke out.

“Members of the public affected by the smoke and unusual odour carried by the wind are advised to close their doors and windows and stay calm,” the government said in a statement.

The warehouse is owned by China Resources Group, but it was not immediately clear what was being stored there. The state-owned company, which runs businesses in areas ranging from healthcare to consumer products such as beer, did not immediately respond to requests for comment.

A Reuters witness said the yellow smoke emanating from the building had a chemical smell, but was not able to identify it. About 3,600 people from nearby residential schools and buildings needed to be evacuated, according to Hong Kong media reports.

A 39-year-old mother came to pick up her nine-year-old son as he waited alone, with police officers nearby. “It’s very smelly,” said the woman, who gave only her surname, Lee. “I am worried about whether there are toxins which will affect my child’s health.” REUTERS