TOKYO: More than 450 people received hospital treatment for heat-related issues in a single day in Tokyo — the highest number since records began 16 years ago, emergency services said Thursday.

The figure was released as Japan sweltered in a heatwave that has killed at least 14 people over the past week.

A total 453 people had hospital treatment for heat-related issues on Wednesday, the most since records began in 2010, the Tokyo Fire Department said. Emergency callouts were also at the highest level since at least 1963.

“We are urging people to stay hydrated and use air conditioners,” a fire brigade spokesman told AFP.

The number of patients appeared to rise as temperatures climbed, with notable increases on Tuesday and Wednesday, the spokesman said.