A deadly heatwave in South Korea has claimed 19 lives since mid-May, according to the Korea Disease Control and Prevention Agency, as the country registered its highest temperature since modern records began. The agency said on Tuesday that 2,221 people had been treated for heat-related illnesses between 15 May and 2 August, though the interior ministry and meteorological administration earlier reported 2,025 cases and 16 deaths, reflecting the rapidly evolving toll.

The record was set on Sunday in the southeastern city of Yangsan, where the mercury reached 42.5 degrees Celsius, surpassing all previous measurements in 122 years of systematic weather observations. The Korea Meteorological Administration subsequently issued its first-ever “severe” heatwave warning for the entire capital Seoul on Tuesday, a designation triggered when the maximum perceived temperature is forecast to reach at least 38C. The alert advises the suspension of all outdoor activities, including farming, construction work and sports.

President Lee Jae Myung, speaking at a cabinet meeting, called the heatwave a national disaster and ordered a fundamental overhaul of the country’s crisis response system. “We need to make efforts for a fundamental overhaul of the national crisis system, since this extreme weather is becoming normal,” he said, according to local media. He also instructed officials to inspect power grids as demand for air conditioning surged. Authorities in Seoul have deployed 200 water trucks to spray nearly 2,000 kilometres of roads, set up 4,000 cooling shelters, and dispatched nurses to monitor 63,000 elderly, disabled and chronically ill residents deemed most at risk.

The extreme conditions have disrupted daily life: two professional baseball games were cancelled, and residents described seeking refuge in air-conditioned spaces. “I never had felt a heat like this here,” said Cho Sang-yeon, a resident of a low-cost housing district in western Seoul. The heatwave has also gripped North Korea, where state media urged citizens to avoid daytime outdoor activity, and Japan, where officials said three lions died of suspected heatstroke at a zoo in Tokyo and earthquake recovery efforts in Kumamoto were complicated by temperatures exceeding 100 degrees Fahrenheit.

The death toll may rise further as the heatwave persists. The Korea Meteorological Administration warned of “extreme, life-threatening heat” and forecast that temperatures would again surpass 40C. The government has acknowledged that the abnormal weather is likely to continue for a considerable period, and the full human cost remains provisional.