Hawaii's Kilauea volcano crater wall collapses, causing lava explosion

Molten lava and rocks went flying through the air on Hawaii's Kilauea volcano after an explosion caused by the partial collapse of a crater wall.

In this May 3, 2015 photo provided by U.S. Geological Survey Hawaiian Volcano Observatory, smoke and lava explode from Kilauea volcano on Hawaiis Big Island. (USGS Hawaiian Volcano Observatory via AP)

Molten lava and rocks went flying through the air on Hawaii's Kilauea volcano after an explosion caused by the partial collapse of a crater wall.

The US Geological Survey's Hawaiian Volcano Observatory says the collapse on Sunday triggered a small explosion, spreading lava and debris around the rim of the crater.

The explosion happened on Kilauea's Halemaumau Crater. Video of the event shows a wall of rocks falling into a lava lake that has been rising over the past week.

The USGS says fist-size chunks of rock were thrown onto the closed Halemaumau visitor overlook.

The area has been closed since 2008 when the lava lake formed, and no one was injured.

A magnitude 3.6 earthquake was felt in the area early on Monday morning, according to the USGS.