Visitors at Yellowstone National Park ran for their lives after an underground hydrothermal explosion.
The eruption was in the national park’s Biscuit Basin area, originating near Black Diamond Pool, located about 2.1 miles northwest of Old Faithful.
Frightening footage shows about a dozen tourists fleeing along the boardwalk leading up to the thermal pools as a massive black mushroom cloud of steam and debris rose hundreds of feet in the air.
Some tourists are seen screaming as large chunks of rock spewed in all directions.
Miraculously, no one was injured in the explosion, according to the United States Geological Survey (USGS), but Biscuit Basin, as well as its parking lot and boardwalks, have been temporarily closed for visitor safety.
According to the USGS, such explosions occur “when water suddenly flashes to steam underground,” saying such events are “relatively common in Yellowstone.”
The federal agency says the explosion is not an indication of volcanic activity and that it wasn’t caused by magma rising towards the surface.
Video taken after the massive plume subsided shows the boardwalk littered with debris as tourists carefully make their way to check out the steaming underground cauldron.
The explosion is under investigation by Yellowstone geologists.
