Mount. St. Helens erupts again

Mount St. Helens in Washington state has erupted, sending a plume of steam and ash 7,600 metres into the air.

View of Mount St. Helens from Portland, Oregon

The volcano has been active in previous months. A minor eruption lasted 24 minutes last October, sending up 3,000 metres of steam and ash.

• FROM OCT. 4, 2004: New steam blast from Mount St. Helens

The U.S. Geological Survey detected magma moving below the surface, along with the increased presence of gases such as carbon dioxide, indicating a violent explosion, but nothing happened.

It grew a dome top 80 stories high in December, which began expanding at a rate never seen before by scientists studying the volcano. Infrared images showed fresh lava was rising at temperatures of almost 800 C.

At the time, scientists said it would take 11 years before erupting the way it did back 1980, when it killed 57 people and covered towns more than 400 kilometres away with ash.

• PHOTO GALLERY: Mount St. Helens eruptions in October 2004

• LINK: U.S. Forest Service: Mount St. Helens webcam

• INDEPTH: Volcanoes