Prime Minister Yoshihide Suga warned Friday of signs of a resurgent spread of the novel coronavirus in Japan as colder weather drives more people indoors.
"We have to watch the situation with a stronger sense of caution than before," Suga said in a session of a Diet committee, a day after new daily infections in Japan topped 1,000 for the first time since Aug. 21.
On Friday, nationwide cases reached 1,141, surpassing the previous day's 1,050 and bringing the cumulative total to 106,827, including around 700 from the Diamond Princess, a cruise ship that was quarantined in Yokohama in February, according to a Kyodo News tally based on official data.
While urban areas such as Tokyo and Osaka have continued to see high numbers, there have also been clusters of infections in the northernmost main island of Hokkaido and northeastern parts of the country.
Experts say this could be due to more people spending time in poorly ventilated rooms as temperatures turn lower.
Hokkaido, a popular tourist destination, confirmed Friday an additional 115 infections. The figure comes a day after a record single-day increase of 119, the first time Hokkaido has reported a daily figure above 100 since the outbreak of the virus.
Hokkaido Gov. Naomichi Suzuki said he will raise the pandemic alert to the third highest of five levels possibly on Saturday, and is also likely to request establishments such as alcohol-serving business operators in Sapporo's famed Susukino nightlife district to shorten their business hours.
In Sapporo, clusters of infections were detected in a high school and a medical institution, the city said Friday.
Chief Cabinet Secretary Katsunobu Kato told a press conference the government was "sparing no effort" to curb further outbreaks, working with local officials to boost virus testing in entertainment districts where many of the clusters have sprung up.
The Tokyo metropolitan government on Friday reported 242 new cases, bringing the capital's cumulative total to 32,135, the highest by far among Japan's 47 prefectures.
Saitama, one of Tokyo's neighboring prefectures, reported a record 114 new cases, of which 32 were due to a cluster of infections detected at a care home in Kawaguchi.
Osaka Prefecture, which has the second-highest cumulative total in the country, confirmed 169 additional infections. The figure is the highest since Aug. 21.