More than 9000 staff and 105 helicopters were deployed to quell the fires engulfing areas mostly in the southeast of the country, damaging residential buildings and a temple, the authorities said.
More than 1500 residents took shelter as the fires wiped out some 6300 hectares of forests, Acting President Choi Sang-mok told a disaster response meeting on Sunday.
"I request that the Korea Forest Service pay special attention to securing the safety of personnel in charge of extinguishing wildfires in the air or on the ground," Choi said as he vowed to use all available resources to stop the fires.
Three of the four people who died were firefighters and one was a public servant, according to the Yonhap news agency.
The largest fires were in the southeast, including the rural county of Sancheong, where 260 people fled to a temporary shelter as flames spread across the surrounding hills, according to the South Gyeongsang provincial government.
The Korea Forest Service said the Sancheong wildfire had burned more than 1200 acres as of Saturday evening.
More than 400 people evacuated their homes in the county of Uiseong in North Gyeongsang province as firefighters continued to fight a blaze that had so far burned 740 acres, according to the forest service.
Dozens of residents also fled their homes in the city of Gimhae.
The fires forced the closures of several highway sections in the country's southeast, including one connecting Ulsan and Busan, South Korea's second-largest city.
The national government designated the North and South Gyeongsang provinces and the southeastern city of Ulsan as disaster zones, and the country's acting president, Choi Sang-mok, vowed an all-out response to extinguish the flames.
Wildfires were also reported in central Chungcheong and southwestern Jeolla provinces.
with Reuters
