The Chinese embassy in Kazakhstan warned its citizens on Thursday of an unidentified strain of pneumonia, after a "significant" rise in cases in June.

"The mortality rate of the disease is much higher than that of pneumonia caused by the novel coronavirus," it said on its official WeChat social media account.

The Chinese embassy described the virus as "unknown," according to the Hong Kong-based South China Morning Post.

Health institutions in the central Asian country were working on identifying the reasons behind the sudden surge in cases.

Kazakhstan, however, dismissed the claim by China's embassy as "fake news."

"The information published by some Chinese media regarding a new kind of pneumonia in Kazakhstan is incorrect," the ministry said.

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Numbers of bacterial, fungal and viral pneumonia infections, which also included cases of unclear causes, were in line with World Health Organisation guidelines, reported Reuters news agency, citing the ministry.

Chinese embassy warns citizens

According to the Chinese embassy statement, there had been a spike in cases in the cities of Atyrau, Aktobe and Shymkent since mid-June.

Shymkent is 1,500km (930 miles) southeast from the regional capital of Atyrau, while the distance between Atyrau and Aktobe is 330km (205 miles).

Pneumonia in Kazakhstan had killed 1,772 people in the first half of the year, with 628 deaths in June alone, including a number of Chinese citizens, the Chinese embassy said.

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On Tuesday, state news agency Kazinform reported an increase in cases of pneumonia in the former Soviet republic – in June more than twice than the same period in 2019.

The Chinese embassy in Kazakhstan urged Chinese nationals in the country to "step up prevention to lower the infection risks."

Struggling to contain coronavirus

Kazakhstan imposed its second lockdown this week in a bid to control the spread of coronavirus. The latest figures show almost 55,000 COVID-19 recorded infections, including 264 deaths.

The number of new cases rose on Thursday to a daily record of 1,962.