A Hawaiian man died after a lava tube collapsed ̵
Police allege that the 71-year-old youth apparently fell about 22 feet (7 m) "through a soft ground".
Lava tubes are formed when the lava cools and solidifies on its top layer, but continues to drain and cool below.
Police say the man was found Monday after friends reported they hadn't heard him in days.
- Lava tubes safe enough for the moon base
Hawaii Police Major Robert Wagner told Big Island Now that the man's pit fell approximately 2 feet (60 cm) wide.
Crews of fire set in the abyss to restore the body.
Unlike slower-growing geological features such as caves and caves, lava tubes often form in days and weeks, according to National Geographic.
As the lava flows and drains into the ocean, it leaves behind labyrinthine tunnels – some of which are over 40 miles long.