Up to 25,000 villagers have been evacuated from the slopes of a rumbling volcano on Indonesia's Sumatra Island (search), though scientists on Wednesday said the mountain was calming down.

The mass exodus from the slopes of Mount Talang (search) reflects in part the nervousness of people living on Sumatra, which has been hit by almost daily earthquakes in recent weeks and was devastated by the Dec. 26 tsunami.

Rumors spread by cell phone text messages have warned of more earthquakes, tsunami waves and volcanic eruptions, adding to the sense of panic on the island.

The 9,186-foot mountain was spewing ash some 1,600 feet into the air Tuesday, though on Monday the ash reached twice as high, said Surono, an official at a government-run volcano center.

"However, we are still monitoring the mountain," said Surono, who goes by a single name.

About 25,000 residents from five villages around the volcano have been evacuated to nearby Solok district, said district chief Djamawan Fauzi (search). Many are returning to their homes during the day to tend crops and look after their animals, another official said.

"The volcano has not yet spewed lava from the crater, but in order to anticipate such an incident, we have evacuated those living around the mountain to safer areas," Fauzi said.

Indonesia's president, Susilo Bambang Yudhoyono, was scheduled to visit the region, some 560 miles northwest of Jakarta, to try and calm the villagers, his spokesman said.

The mountain is among at least 129 active volcanoes in Indonesia, the world's largest archipelago nation. The country is part of the Pacific "Ring of Fire" -- a series of volcanoes and fault lines stretching from the Western Hemisphere through Japan and Southeast Asia.

They regularly smoke and rumble, but panic on the scale generated by Talang's eruption is rare.