According to Kyodo News Agency, Japan's Fire and Disaster Management Agency said extreme heat left 77 people dead and sent more than 30,000 to hospitals across the nation from July 9 to 22.
In a news conference on Tuesday, the country's Meteorological Agency said: "This heat is life threatening. We recognize it as a natural disaster."
On Monday, in Kumagaya located north of capital Tokyo, temperatures hit a record high of 41.1 Celsius. The Meteorological Agency warned people to take preventive measures against a possible heatstroke as they expect the deadly heatwaves to continue for two more weeks.
During the first two weeks of July, 30 people lost their lives from the heat wave while more than 12,000 were rushed to hospitals due to health problems emerging from high temperatures.