Officials in Tokyo are concerned about the more transmissible BA.2 Omicron coronavirus subvariant, which is increasingly dominant among infections.

The capital's expert panel says its screening indicates the BA.2 subvariant accounted for nearly 68 percent of new cases in the week through March 28. The rate has climbed nearly 30 points in the past two weeks.

Tohoku Medical and Pharmaceutical University Professor Kaku Mitsuo said, "We are at a critical moment where infections will rapidly spread or not." He added, "We have to take measures to prevent it from happening."

More than 8,700 new cases were reported in Tokyo on Thursday. Case numbers have leveled off, after peaking in February.

Nearly 55,000 new cases were reported across Japan. Infections appear to be spreading again in some prefectures, including Fukushima, Kagoshima and Niigata. They recently reported their highest numbers.

Infections are surging among people aged 10 to 29. Experts point to the lower rates of third vaccinations in this age group.

Prime Minister Kishida Fumio says the government will provide subsidies for group vaccination programs jointly conducted by local authorities and universities.

Kishida said, "The government will promote group vaccinations for students by making use of large-scale vaccination venues in municipalities where reservations are available." He also said, "The government will help cover the costs."

The Tokyo Metropolitan Government is set to launch group vaccinations for companies and universities. They can make reservations if they have 10 or more employees or students. Applications will open starting Monday.