Olympic host city Tokyo registered a record 3,177 new coronavirus cases on Wednesday (local time), authorities announced, as rising infections put pressure on hospitals amid the hype of the Games.
The rise adds worries about the completion of the Games, which are taking place under unprecedented sanitary conditions including a ban on spectators in most venues.
It also spells trouble for Prime Minister Yoshihide Suga, whose support ratings are at their lowest since he took office last September, ahead of a ruling party leadership race and a parliamentary election this year.
Nationwide, the number of new Covid-19 cases exceeded 9,000 for the first time, according to public broadcaster NHK's calculations.
More emergency declarations for Japan
Governors of three prefectures near Tokyo — Kanagawa, Chiba and Saitama — will ask the government on Thursday to declare states of emergency for their regions, Economy Minister Yasutoshi Nishimura, who leads Japan's Covid-19 response, told a parliamentary panel.
"I think we've entered a trend of sharp rises in cases, which I had feared the most," Kanagawa governor Yuji Kuroiwa told reporters.
Tokyo is under its fourth state of emergency, which is due to last through the Olympics, while the other three regions are implementing "quasi-emergency" measures.
However, while many other countries have at times imposed severe social and economic lockdowns, Tokyo's measures rely mainly on asking restaurants that serve alcohol to shut their doors, and others to close by 8 pm.
Olympic Games Covid cases rise to 169
Olympics organisers reported 16 new Games-related cases, for a total of 169 since July 1. Athletes, staff and media must all follow strict rules, including frequent testing, inside an "Olympic bubble".
Many Japanese are worried about a spread of infections from Games participants.
Suga on Tuesday urged people to stay home as much as possible and watch the Olympics on television.
But senior opposition Constitutional Democratic Party lawmaker Jun Azumi said the government was being too optimistic.
Japan's health system on brink of collapse
"Unless it revises its view of the infection situation, after the Olympics end, there will be a serious national crisis affecting people's lives, beginning with a collapse of the medical system," the NHK public broadcaster quoted Mr Azumi as saying.
Japan has avoided the devastating outbreaks suffered by other countries such as India and the United States, but its fifth wave of the pandemic is straining hospitals.
Many Japanese have grown weary of the largely voluntary restrictions and some experts say the decision to go ahead with the Olympics sent a confusing message, posing a greater risk than any direct spread from Olympic participants.
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