A Japanese man in his 40s has died in the Chinese municipality of Chongqing after testing positive for COVID-19, government officials said Friday, as Beijing grapples with an apparent surge of infections after a major easing of its strict antivirus measures earlier in the month.

The Japanese Consulate General in the southwestern Chinese city confirmed his death on Monday. The male employee of a Japanese company had been quarantined at home.

A medical worker wearing protective gear is pictured at a hospital in Beijing in the early hours of Dec. 20, 2022, amid a rise in COVID-19 infections. (Kyodo) ==Kyodo

In Tokyo, Chief Cabinet Secretary Hirokazu Matsuno said earlier in the day at a press conference the Japanese government has been offering support to his family.

Chief Cabinet Secretary Hirokazu Matsuno holds a press conference in Tokyo on Dec. 23, 2022. (Kyodo)

A medical research firm based in Britain has estimated that the daily COVID-19 death toll in China now probably tops 5,000 and that new infections exceed 1 million a day, using modeling based on regional Chinese data.

The estimates were "in stark contrast to the official data which is reporting 1,800 cases and only seven official deaths over the past week," Airfinity Ltd. said in a statement on Thursday.

Since China significantly relaxed its "zero-COVID" policy on Dec. 7, it has stopped requiring people to take frequent PCR tests and releasing data on asymptomatic cases.

People who died after chronic illnesses deteriorated due to COVID infection may not be included in the official death counts in China based on a government notice, according to local media reports.

Airfinity said cases are currently rising much more quickly in Beijing and southern China's Guangdong Province and could reach 3.7 million a day in a January peak and then 4.2 million a day in March as the virus spreads to other regions.

U.S. media Radio Free Asia said Thursday the cumulative number of virus infections in China between Dec. 1 and Tuesday reached 248 million, accounting for some 18 percent of the total population, based on a leaked document.

The minutes of China's National Health Commission meeting on Wednesday leaked online showed cumulative infection rates have exceeded 50 percent in Beijing and Sichuan Province in the southwest.

On Wednesday alone, new infections across the country were estimated to have approached 37 million.

The document warned the situation will become more serious with the expected large-scale movement of people during the Chinese New Year holidays in late January, which would spread infections in both cities and rural areas.

On Friday, many boxes believed to be caskets were lined up at a central Beijing hospital, where a fever clinic was crowded with patients.

Hong Kong's South China Morning Post said Friday hundreds of health care workers including those specializing in critical care have been sent to Beijing from other parts of the country to ease the burden at heavily strained hospitals amid the surge of infections.

Chinese tech giant Tencent Holdings Ltd. has launched a smartphone app for drug-sharing among citizens amid a lack of cold medicines, with many users appealing their plight and calling for help in their posts.

Since the launch of the service earlier this week, the platform has seen some 270,000 posts from citizens, according to Chinese media.