The most lethal avalanches, called pyroclastic flows - clouds of superheated rock, ash and gas, race down the slopes of the volcano at speeds that can exceed 100 mph. But the avalanches caused by this eruption were small in comparison to those that killed at least 10 people during the earlier eruption on 25 June. Another nine people are still missing, and feared dead. Last week, Britain said it would conduct polls among Montserratians about whether they wanted to abandon the island. Old Towne, Montserrat - AP
Montserrat's volcano yesterday began to erupt without warning, sending explosions of ash across the entire island and setting off small avalanches of rock and gas in the evacuated south, prompting the government to broadcast messages urging people to "remain at a high level of preparedness and alert".