Anak Krakatau, built on the same lava plume as the Krakatoa volcano that killed tens of thousands in 1883, continued to spew lava, hot gas and rocks Thursday into the Sunda Strait between the Indonesian islands of Java and Sumatra.

Anak Krakatua, or "Child of Krakatoa" in the official Indonesian language, rose from the water in 1930 at the same spot where Krakatoa had blown itself apart.

Elsewhere in Indonesia, the government lowered the alert status of the Kelud volcano, meaning that thousands of people who fled its slopes for government shelters can return home.

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Mount Kelud on the densely populated island of Java had been on top alert for several weeks.

"The volcano no longer has the energy needed for an explosive eruption that would threaten the lives of people living nearby," Surono, the chief volcanologist at the government's volcano agency, said on the decision to downgrade Kelud's status.

Like many Javanese, Surono uses a single name.

In 1990, Kelud spewed searing fumes and lava that killed more than 30 people and injured hundreds. In 1919, a powerful explosion that reportedly could be heard hundreds of miles away killed at least 5,160.

Thousands of people from villages close to Kelud's crater lake had earlier heeded evacuation orders and moved to tent camps or government buildings, though many ignored the warnings and remained in the danger zone.

The government volcano agency said Kelud remained on the second-highest alert level and told villagers to remain vigilant because the mountain was very unpredictable. It said that villagers could return home, but should not venture close to the crater, which was still emitting smoke.

Indonesia is prone to volcanic eruptions and earthquakes because of its location on the so-called "Ring of Fire" — a series of fault lines stretching from the Western Hemisphere through Japan and Southeast Asia.

It has around 100 active volcanoes.