MORONI, Jan 18 (Reuters) - Comoros' largest island shook twice on Thursday, residents said, and experts said there was still a threat of eruption from the Indian Ocean archipelago's Mount Karthala volcano despite the tremors weakening.

Comorian authorities have made emergency plans to help as many as 30,000 people in case the 2,361 metre (7,746 ft) volcano, which dominates the main island of Grand Comore, blows.

"I felt very faint tremors in the morning and at three o'clock," resident Mounira Boba said. "But I'm not so worried."

The volcano seemed to have settled since the weekend when strong tremors -- thought to have been caused by lava trying to escape -- forced thousands of people to sleep outside for fear their homes might collapse.

Mount Karthala, one of the world's largest active volcanoes, began glowing red and emitting fumes last week.

Scientific equipment has continued to record more than a thousand small tremors every day, officials at the Karthala observation centre said. Residents cannot feel such tremors.

Patrick Bachelery, a vulcanologist and academic from the nearby island of Reunion, warned Grand Comore residents not to drop their guard.

"Even if activity quietens down, it could be a sign of eruption," he said.

Karthala's eruptions have happened every 11 years on average, but have rarely caused a major disaster.

In 1903, 17 people died when noxious fumes seeped from cracks in the mountain, and the last big eruption was in April 2005 when thousands fled in fear of poisonous gas and lava.

AlertNet news is provided by

Delicio.us  |   Digg  |   NewsVine  |   Reddit                                                                                  Permalink