Okinawa on Wednesday asked the central government to join a COVID-19 state of emergency already covering Tokyo and other areas, as infections in the southern island prefecture rose to a record high.

The prefecture reported 203 daily new infections among its population of 1.5 million, up from 168 the previous day, with Okinawa Gov. Denny Tamaki saying the local health care system is in a "crisis situation."

Prime Minister Yoshihide Suga has declared a state of emergency in nine prefectures until May 31, with restaurants and bars being told to close by 8 p.m. and refrain from serving alcohol or offering karaoke services.

Department stores and other major commercial facilities are also requested to temporarily shut or close early, and attendance at concerts and sports events has been capped at 5,000 or 50 percent of venue capacity.

Japan is in the midst of a fourth wave of infections just over two months before the Tokyo Olympics kick off, with a total of 5,820 new coronavirus cases reported nationwide on Wednesday. According to the Ministry of Health, Labor and Welfare, there were a record 1,293 COVID-19 patients in serious condition.

The situation in some areas under the state of emergency has improved, with new coronavirus cases in Osaka down to 477, less than half of what it was seeing at the beginning of May, though an expert panel at the health ministry warned of a possible rebound as more people were beginning to go out and about.

Meanwhile, the country's vaccination program has lagged, with just about 4 percent of the population having received at least one shot as of Tuesday, according to government data.

At present, 16 municipalities in Okinawa are under a quasi-state of emergency, which allows the governor to single out areas with such anti-virus measures as telling restaurants to close early. By comparison, a full-fledged emergency declaration covers an entire prefecture.

Chief Cabinet Secretary Katsunobu Kato said the situation in Okinawa warrants "watching with a sense of caution" and that the government will quickly review the prefecture's request to join the state of emergency areas.

A popular tourist destination for its warm climate, beaches and distinct Ryukyu culture, Okinawa also hosts the bulk of the U.S. military presence in Japan.