Indonesian authorities said Saturday that Mount Kelud did not erupt as they had earlier reported, but cautioned residents that the deadly volcano remained on the highest alert level.

Government scientists had said that seismic monitors on Kelud's slopes detected continuous tremors and a spike in the temperature of its crater lake, indicating an eruption had begun.

The scientists, who fled their posts on the volcano, were unable to visually confirm the eruption because the peak on the densely populated island of Java was clouded in fog.

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But Surono, a senior government volcanologist who goes by a single name, told el-Shinta radio station late Saturday "in reality Kelud did not erupt," noting that monitoring equipment close to the crater was still working.

News of the apparent eruption on Saturday afternoon triggered the evacuation of scores of people, including women hauling babies in slings, from the mountain in police trucks and on motorcycles, witnesses said.

"I am afraid because the authorities say this eruption will be worse than the ones that have come before," said Marsini, a villager living just five kilometers from the crater. "They say there may be poisonous gas. I am leaving now."

Surono said Kelud remained on the highest alert level, meaning scientists fear an eruption is imminent. They fear any eruption may be large, given the signs so far. But they also note it could be small — or may not happen at all.

In recent weeks, several thousand people have already been evacuated from villages closest to the crater, but an unknown number are believed to be still in the danger zone, ignoring warnings.

In 1990, Mt. Kelud killed more than 30 people and injured hundreds. In 1919, a powerful explosion that could be heard hundreds of miles away destroyed dozens of villages and killed at least 5,160.

Scientists fear a buildup of magma under Kelud's crater lake could trigger a violent blast, sending a torrent of mud, ash and rock careering down the side of the 1,731-meter (5,679-foot) mountain.

For weeks, authorities have pleaded with villagers to move to tent camps or government buildings, but have faced resistance. Many people have insisted on staying behind to tend to crops or look after their houses.

Some apparently believe a local myth, which claims that if residents turn off all the lights and speak softly, then the mountain won't erupt.

Indonesia has about 100 active volcanos, more than any nation.

The country is spread across 17,500 islands and is prone to volcanic eruptions and earthquakes because of its location within the so-called "Ring of Fire" — a series of fault lines stretching from the Western Hemisphere through Japan and Southeast Asia.

At least three volcanoes are currently erupting elsewhere in the country, including Mount Anak Krakatau, which lies off the northern tip of Java island. The mountain was formed after the famous Krakatau volcano erupted in 1883, killing thousands, but it is not seen as at risk of a major blast.