Four new fires are burning at the site in the Chinese city of Tianjin where blasts killed at least 116 people, the state-run Xinhua news agency says.
One of the fires started at an automobile distribution site not far from the epicentre of the blasts.
Three other fires were burning within the core blast site, and rescue crews have been dispatched to the scene.
Sixty people are still missing after the 12 August blasts, which also injured at least 700.
Thousands of people saw their homes destroyed or made too unsafe to return to. Authorities have promised to compensate residents.
The blasts happened at a warehouse storing hazardous chemicals in Tianjin’s port. What caused them is still unclear and a massive clean-up is continuing, with thousands of police and soldiers deployed.
One of the new fires was reported to be in the depot where at least 3,000 cars were incinerated and may have been caused by leaking fuel.
Officials say the blast site is contaminated by more than 40 dangerous substances, among them the highly toxic sodium cyanide.
Thousands of dead fish have washed up in Tianjin’s Haihe river, a few kilometres away from the blast site.
The Chinese authorities say the fish were killed by low oxygen levels in the water – a seasonal occurrence.
However, many in the area suspect the fish may have been killed by cyanide poisoning, the BBC’s Celia Hatton reports from Beijing.
The warehouse, owned by Ruihai International Logistics, was less than 1km (0.6 miles) from at least three residential complexes, flouting Chinese law.
Facing continuing public fury, local authorities have in recent days been giving more information on chemical contaminants in waste water and in the air.
However, the full list of chemical names has not been released.
The government says that the person in charge of warehouse logistics is too badly injured to speak, making it difficult to know exactly what was inside the warehouse at the time of the blast.