A train staff gestures at an empty station on April 13 in Tokyo. (AP Photo)

Males and those aged 70 or older account for the most deaths from complications of COVID-19 in Tokyo, an analysis by The Asahi Shimbun shows.

Known cases of infection from the deadly virus in Tokyo on April 12 hit the 2,000 mark, the highest among the nation's 47 prefectures.

By age group, those in their 30s accounted for the largest number of infections at more than 20 percent.

Of 42 people who died of the coronavirus or complications from it, many were aged 70 or older.

The Asahi Shimbun scrutinized data released April 12 by the Tokyo metropolitan government for its findings.

The first known case of COVID-19 in Tokyo occurred in late January. The infected person was a visitor from Wuhan, China, where the virus is believed to have originated.

The first Tokyo resident to test positive for the virus was a male taxi driver in his 70s on Feb. 13. He had attended a New Year party for independent taxi drivers held on a yakatabune leisure boat in the capital in January.

Other taxi drivers present on the social occasion, as well as staff on the boat, later tested positive one after another.

The infection rate continued to spread in the capital and 37 people had tested positive by the end of February. The largest age group was those in their 70s, with 10 people infected.

Around mid-March, the infection rate started to spike with people returning from overseas.

The total number of patients reached 102 on March 17.

Around that time, it emerged that cases where the infection route could not be traced started to increase. The total number of patients reached 521 as of March 31.

Cases of in-hospital infection began to rise as well. On March 24, officials in the capital's Taito Ward revealed that a mass infection cluster had occurred at Eiju General Hospital.

As of April 12, 184 people, including hospital staff and in-patients, had tested positive and at least 20 had died.

The number of COVID-19 patients in the capital surpassed 1,000 and reached 1,032 on April 5.

On April 12, news of an infection cluster at Nakano Egota Hospital in Nakano Ward shocked the capital. A total of 92 in-patients, doctors and nurses tested positive.

That brought the total number of infected people in the capital to 2,068.

The metropolitan government on April 13 admitted it had erred in its tally and that the actual number of infected people as of the day before was 2,067.

The Asahi Shimbun analysis looked at confirmed patients in Tokyo by age group. In three cases, the age of the individuals was not available.

The largest group of infected people was among those in their 30s with 423 cases, accounting for 20.5 percent of the total.

This was followed by those in their 40s with 375 cases, accounting for 18.1 percent of the total.

Those in their 20s came to 342, or 16.5 percent. Those in their 50s came to 317, or 15.3 percent. Those in their 60s came to 216, or 10.4 percent.

Those aged between 10 and 19 totaled 29. Eighteen were children under the age of 10, including preschoolers, who had severe symptoms.

Males accounted for 61.6 percent of the total number of patients, with 1,273 cases. The gender of 20 people was not available.

Of the 42 people who died of the virus, the age and gender of four people were not available.

Those in their 70s accounted for the largest group with 14 cases, or 33.3 percent of the total.

This was followed by those in their 80s at nine cases, or 21.4 percent of the total.

Those aged 70 or older accounted for 16.7 percent of infected people, but fatalities in that age group constituted 69 percent of deaths, or 29 out of the 42.

This suggests that older people tend to develop severe symptoms.

Deaths among males reached 29, or about 70 percent of all fatalities.