An explosion occurred at Hawaii's Kilauea volcano after the partial collapse of a crater wall - sending molten lava, rocks and gas flying through the air.

The U.S. Geological Survey's Hawaiian Volcano Observatory says that the collapse caused a small explosion, which spread lava and debris around the rim of Kilauea's Halemaumau Crater, reports ABC News.

USGS geologist Janet Babb compared Sunday's blast to taking a hammer to the top of a champagne bottle, saying, "you look at the bottle and you see the liquid, but you don't see the gas. There's a lot of gas in the lava. And so, when that rock fall hits the lava lake, it's like the moment you knock the top of the champagne bottle off and that gas is released and it hurls molten lava and rock fragments."

Babb further said that rocks overhanging the lava lake are altered by gases from the lava, hence causing an explosion when the rocks eventually gave way and collapsed into the lava. The materials were flung approximately 280 feet skyward.

The slide also caused an explosion that sent fist-sized rock chunks onto the closed Halemaumau visitor outlook, says the Geological Survey. The area has been closed since 2008, when the lava lake formed, and no one was reported injured.

"As long as magma supply is elevated, we expect continued high lava lake levels accompanied by additional overflows," noted an observatory scientist to ZME Science. "We expect continued rockfalls, intermittent explosions and ash fall, and continued high levels of gas release."

Molten lava was last visible in the crater in 1982, when a fissure erupted, while the last time a lake similar to this one existed was in 1974.

The vent within the Halemaumau Crater reached a record high last week, after rising and falling since it first opened. Its previous highest level was in October 2012, and even then, the lake was still too low for people to see. People could view gas rising from the lake at daytime, while an orange glow can be seen at night.

At the same time, the Geological Survey says that a magnitude 3.6 earthquake was felt in the area early Monday morning, reports KHQ.