Firefighters are still working today to contain the fire that erupted in a mountainous national park in Tenerife, with authorities evacuating at least 3,800 people.

The perimeter of the fire it reached 31 kilometers of forest land burning and areas with low vegetation in steep gorges, near the volcano of Mount Teide – the highest mountain in all of Spain – blocking access to the area and covering much of the Spanish island with clouds of smoke and ash.

“When you go outside, the atmosphere is suffocating. It feels like something is stuck in your throat,” said Alba Hill, 37, a resident of the village of La Esperantha, where authorities ordered people to stay indoors because of the thick smoke. Hill and her family stayed up until 4 a.m. worrying about the flames burning up the mountain.

The fire that broke out yesterday Wednesday has already burned 6,425 acres.

“The night was very difficult… This is the most complex fire we have had in the Canary Islands in the last 40 years,” Fernando Clavijo, an executive of the regional government, said during a press conference.

Pedro Martinez, head of emergency services, said the fire spread to the north of the island and to a valley where several campsites are located.

While some villages were evacuated as a precaution, some 3,500 residents in some others were ordered to stay in their homes.

A prison and an immigration reception center are located in those areas where movement restrictions are in place, Clavijo said.

Civil Protection forces today removed 1,294 people from their homes in the municipality of El Rosario and 1,525 from areas of La Orotava. A total of 3,800 have been removed from their homes and many settlement evacuations are still taking place.

Spanish authorities have deployed 17 aircraft and a total of 350 fire and military personnel. Additional firefighting seaplanes arrived from the mainland.

All access to the island’s mountains, including the tourist favorite Mount Teide, has been blocked.

Both Tenerife airports are operating as normal, according to Spain’s national airport management company AENA.

Last week, a new heat wave dried up vegetation in many areas of the Canaries, increasing the risk of wildfires.

Already this summer the Spanish fire brigade has been called to deal with several fires in Gran Canaria and La Palma, two other islands of the Canary archipelago.