Japan’s capital has had temperatures above 31C for two weeks, prompting fears for 2020 Games’ athletes

Heatstroke is suspected in the death of a worker at a Tokyo Olympics construction site, NHK national television has said, as the Japanese capital swelters through a scorching weather that has killed dozens of people.

Soaring temperatures have killed at least 57 people across Japan from 29 July to 4 August, highlighting the health threat to athletes and fans that is one of the biggest challenges for Olympics planners.

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