A fire broke out on Tuesday in Guryong village, a shantytown in Seoul's upmarket Gangnam district, affecting 77 households and 107 people, South Korea's Yonhap news agency said.
No injuries or casualties had been reported, a fire official told Reuters, and Yonhap said people had evacuated to an emergency shelter.
The fire agency has deployed 232 personnel and 70 vehicles to fight the fire, which began at about 3:50 pm local time (0650 GMT) in a temporary structure, Yonhap said. Six helicopters were sent to stop the fire spreading to a nearby mountain.
Guryong, often described as Seoul's largest remaining shantytown, emerged in the 1970s and 1980s when families displaced by public works projects settled on the edge of Gangnam without permits. Its densely packed homes are built with flammable materials such as vinyl sheets and plywood.
A major fire in the village in January forced hundreds of residents to evacuate.
Jordan says it killed more than 20 IS militants in airstrikes on Syria
Two men charged in UK with helping Iran over RAF Fairford incident
Netanyahu's political survival on the line as Israel votes
Congo's Ebola cases surpass 10,000 as fears grow of wider African spread
Indian media groups decry Modi’s privacy law in court, say newsrooms face shutdown risk
