January 9, 2007—Smoke signals don't get much more ominous. A volcano on the island of Montserrat discharged a five-mile-high (eight-kilometer-high) cloud of superheated ash and gas yesterday—possibly portending another, disastrous eruption.

"I think it was a warning call … of what it can do," Vicky Hards, director of the Montserrat Volcano Observatory, told the Associated Press.

Residents have good reason to fear the Soufriere Hills volcano, given that in 1997 it wiped out the tiny Caribbean island's evacuated capital, Plymouth, killing 19 people and prompting an exodus of about half the island's population of approximately 10,000.

This week the crater's lava dome continues to grow—a process that began on December 24. Because yesterday's eruption failed to cause the lava shell to collapse, experts are worried that the mounting pressure could be released in a powerful blast.

Such an eruption would likely send hot ash and gas flying down the northwestern flanks of the mountain. As a result, the U.K. territory's government yesterday ordered dozens of families in the area to evacuate.

—Ted Chamberlain

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