Aug. 5 (UPI) -- With just four days left in the 2020 Summer Olympics, Tokyo has again reported a record number of COVID-19 cases, officials said Thursday.
Health officials said there were slightly more than 5,000 new cases in the city on Wednesday, a figure higher than any other single day since the start of the pandemic.
In Japan, there were close to 15,000 new cases nationwide.
Officials say coronavirus variants, like the Delta strain, are part of the reason for the rise in cases. Similar surges are being seen in countries around the world.
The surge led the Japanese government on Thursday to expand states of emergency to eight more prefectures.
"With the increase of those infected, the number of patients in serious condition is also on the rise."
New daily records for cases were also seen in Kanagawa (1,800), Saitama (1,200) and Okinawa (600) prefectures.
In Tokyo, more than half of new cases involved young people -- 1,600 among those in their twenties and 1,100 in their thirties.
People over 65, who at one point were considered to be at the greatest risk, comprised less than 200 of the new cases in Tokyo.
The Tokyo Olympics, which began on July 23, run through Sunday. Organizers said on Wednesday that the first cluster of the Games was found in multiple athletes from Greece.