The Tokyo metropolitan government reported 1,979 new daily COVID-19 cases on Thursday, a day before the Olympic ceremony and the highest number since mid-January, as fears grow that the games could become a superspreader event amid the transmission of the highly contagious Delta coronavirus variant.

Travelers leave Tokyo from Haneda airport amid heightened coronavirus fears on July 22, 2021, the start of a four-day long weekend specially set for Tokyo Olympic opening ceremony the next day. (Kyodo) ==Kyodo

The Olympic opening ceremony will be held on Friday without fans due to coronavirus restrictions in the capital, which is currently under a COVID-19 state of emergency declared amid surging infections.

In mid-January, Tokyo was under a second state of emergency.

The latest figure represents an increase of 671 from Thursday last week, bringing the seven-day rolling average of cases to 1,373.4 per day, up 55.7 percent from the previous week.

Health experts have warned of a possible "critical" coronavirus situation in Tokyo and that a "fifth wave" of infections is under way.

They have also estimated that daily infections could hit a record of around 2,600 in early August. The Olympics will run until Aug. 8.

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