Truck driver Lee Seung-joo was driving through South Korea's Andong mountains when the wildfires hit, engulfing the area in flames and turning it into "a literal hell."

The 39-year-old added "it was like the apocalypse," as he recalled seeing the fire tear through the area, which, even before the inferno struck, had been suffering from a particularly dry spell.

"The mountain burning looked like literal hell," he added.

Some 27,000 people in the southeast were forced to evacuate from the wildfires, which have been burning continuously for five days, fanned by high winds and fueled by the super-dry conditions.

Sections of National Route 7, the main east coast highway, descended into chaos as the fires caught up with evacuees stuck in traffic jams, struggling to escape.

"Fireballs rained down like rain between the jammed vehicles, setting cars on fire," one eyewitness told local media.

"Drivers barely escaped from the burning cars - it was utter chaos."

Apple farmer Cho Jae Oak, 75, who fled from his property, said that he also saw fireballs flying down from the mountain.

He and his wife had sprayed water to try and save their farm but were eventually forced to escape.

Some evacuees sheltering in an elementary school gym said they had to flee so quickly they could bring nothing with them.

"The wind was so strong," Kwon So Han, a 79-year-old Andong resident said, adding that as soon as he got the evacuation order he fled.

"The fire came from the mountain and fell on my house," he said. "Those who haven't experienced it won't know. I could only bring my body."

At least 24 people have been killed so far, some of whom died during the evacuation process, the Korea Forest Service said.

Authorities said the multiple fires had caused "unprecedented damage" and warned it could still get worse.

Authorities had been using helicopters to battle the blazes, but suspended all such operations after a helicopter crashed yesterday, killing the pilot on board.

Authorities said changing wind patterns and dry weather had revealed the limitations of conventional firefighting methods.

Agence France-Presse Reuters

Reuters

S Korea wildfires 'like the apocalypse'