A large sulfur dioxide gas cloud is blowing toward Keflavík International Airport. Authorities have told people nearby to stay indoors and keep their windows shut as pollution levels rise. Despite this, flights are running normally and the airport remains open.

Volcanic activity on southwestern Iceland's Reykjanes Peninsula is declining, prompting civil protection authorities to lower the alert level from "emergency" to "threat," Icelandic public broadcaster RUV reported Thursday.

Some people have reported seeing so-called “ witch’s hair ” drifting in the air. These are fine, sharp, glassy needles that are formed in volcanic eruptions when lava droplets rapidly cool and stretch. Because they are light, these glassy fibers can travel long distances and can cause skin and eye irritations.