A fire near the Grand Canyon National Park in Arizona has grown more than 20 times in size in 24 hours as an intensifying wildfire season sees the return of Canadian wildfire smoke into the U.S.

Visitors and staff at two national parks in the U.S. West have been evacuted because of wildfires. Officials at Black Canyon of the Gunnison National Park in Colorado say the park closed Thursday morning after lightning sparked blazes on both rims.

A historic lodge on the Grand Canyon’s North Rim has been destroyed by a fast-moving wildfire, the park said Sunday.

Dozens of buildings inside the North Rim of the Grand Canyon have been destroyed, including a historic lodge, as a chlorine gas leak has forced firefighter evacuations from the Dragon Bravo Fire.

A Grand Canyon water treatment facility located at the North Rim caught fire on Saturday, causing chlorine gas to be released into the air. Multiple closures are being enforced due to the incident.

Authorities maintained the evacuation zones for the White Sage Fire north of the Grand Canyon as the fire grew expectantly.