Some 242 deaths from the new coronavirus were recorded in the Chinese province of Hubei on Wednesday – the deadliest day of the outbreak.
There was also a huge increase in the number of cases, with 14,840 people diagnosed with the virus.
Hubei has started using a broader definition to diagnose people – which accounts for most of the rise in cases.
China sacked two top officials in Hubei province hours after the new figures were revealed.
Until Wednesday’s increases, the number of people diagnosed in Hubei – where the outbreak emerged – was stabilizing.
But the new cases and deaths in the province have pushed the national death toll above 1,350 – with almost 60,000 infections in total.