BALI, Indonesia -- More than 35,000 people have fled a menacing volcano on the Indonesian tourist island of Bali, fearing it will erupt for the first time in more than half a century as increasing tremors rattle the region.

The numbers Sunday from disaster officials are more than double previous estimates and are continuing to rise, they say. It includes people who left voluntarily as well as those told to evacuate from a 6-8 mile zone around Mount Agung.

Authorities raised the volcano's alert status to the highest level Friday following a "tremendous increase" in seismic activity. Its last eruption in 1963 killed 1,100 people.

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Luhut Binsar Panjaitan, a senior Cabinet minister, said Sunday that the districts surrounding the volcano "must be prepared for the worst."

The National Disaster Mitigation Agency has praised the welcoming response of local communities on Bali to the flood of evacuees.

Thousands are living in temporary shelters, sport centers, village halls and with relatives or friends. Some return to the danger zone during the day to tend to livestock.

A boy sits amongst his family belongings at a temporary shelter in Rendang, on the resort island of Bali, after he was evacuated from a village located along the slopes of Mount Agung. Reuters

National Disaster Mitigation Agency spokesman Sutopo Purwo Nugroho said 14 tons of aid has been sent, including tents, blankets, mattresses and portable communications equipment.

Truck driver Wayan Suparta said he and his family left their village 3 miles from the mountain several days ago, bringing just clothes and blankets to a temporary camp in Rendang. The 35-year-old said he sold the family's cow because they don't know when they'll be able to return.

Officials have said there is no current danger to people in other parts of Bali, a popular tourist island famous for its surfing, beaches and elegant Hindu culture.

Hoaxes have proliferated online, with videos of previous eruptions in Indonesia circulated as current events at Mount Agung.

In 1963, the 9,944-foot Agung hurled ash as high as 12 miles, according to volcanologists, and remained active for about a year. Lava traveled 4.7 miles and ash reached Indonesia's capital, Jakarta, about 620 miles away.

The mountain, 45 miles to the northeast of the tourist hotspot of Kuta, is among more than 120 active volcanoes in Indonesia.

The country of thousands of islands is prone to seismic upheaval due to its location on the Pacific "Ring of Fire," an arc of volcanoes and fault lines encircling the Pacific Basin.