SEOUL, South Korea (AP) — A forest fire burning in the mountainous region where South Korea hosted the 2018 Winter Olympics has destroyed 120 homes and caused two deaths, authorities said Friday as thousands of people fled.

The fire likely started Thursday night from a transformer spark near a resort in the town of Goseong in Gangwon province about 210 kilometers (130 miles) northeast of Seoul and then spread to the nearby mountains, according to Choi Jin-ho, a fire captain at Gangwon Fire Headquarters.

Videos posted to social media in South Korea showed tall flames shooting from large areas of forest, the air filled with embers and debris as cars drove by the raging fire. News photos showed a burnt-out bus, fire engulfing a hill, and residents evacuating apartment complexes and filing into gyms.

Choi said nearly 2,400 people in Goseong and almost 1,250 in the town of Sokcho have been evacuated. He said a 60-year-old man and a woman in her 70s died.

Strong winds spread the fire rapidly in the forested mountains, and the Ministry of the Interior and Safety said about 250 hectares (1 square mile) of forest had burned as well as 120 homes.

About 20 firefighting helicopters and 5,600 firefighting personnel were expected to be deployed Friday, the ministry said. The fire also spread toward Ganeung and Donghae, causing the temporary shutdown of a highway and delays in train services from Ganeung to Seoul.

Another Gangwon fire official, who spoke on condition of anonymity because of office rules, said at least 11 people were being treated for injuries. The official wouldn't comment on the nature of the injuries or how many were serious.

The office of South Korean President Moon Jae-in said he held an emergency meeting early Friday and called for all available resources to be deployed. Moon instructed officials to aggressively inform and evacuate residents and also to consult with North Korea to fight the fire in case it spreads north of the border.

Choi said nearly 800 firefighters were fighting the fire overnight, but they were having trouble because of the wind and darkness, which prevented the use of helicopters.

Fire brigades from all major surrounding regions, including Seoul, were reportedly ordered to send trucks to help fight the blaze.

Gangwon province governs Pyeongchang, the city that hosted the Winter Olympics more than a year ago.