Scores of people who had returned to a Chilean town destroyed by a volcanic eruption are being evacuated again as the volcano roared back to life.

Officials say an explosion rocked the dome of the Chaiten volcano. Lava and ash threaten to block a river and cause flooding.

The government warns avalanches that could occur due to rain. As many as 150 people will be moved from the town at the foot of the 960-meter volcano.

The town of Chaiten was devastated last May when the nearby volcano of the same name erupted. The town was covered in ash and damaged by flooding from the ash-choked Blanco River.

(CCTV February 20, 2009)