South Korea's weather agency said a heat wave warning remained in effect for most parts of the country Sunday, warning people to refrain from outdoor activities as temperatures soared to 33 C in most areas.

The heat wave warning first went into effect for most parts of the country Tuesday, according to the Korea Meteorological Administration.

On Sunday, the agency raised a heat wave advisory in some parts of Gyeonggi Province and South Jeolla Province to a heat wave warning.

Heat wave warnings are issued when the highest apparent temperature is expected to be 35 C or higher for more than two consecutive days or if major damage is anticipated from the heat.

The midday temperature rose to 35 C in Seoul, Daegu, Gangneung and Cheongju, while most of the country saw the mercury rise to 33 C.

The KMA advised the public to refrain from outdoor activities and urged those working outside to stop working between 2 p.m. and 5 p.m.

On Saturday, four heat-related deaths were reported in North Gyeongsang Province, according to the provincial fire authorities.

Source: Yonhap News Agency