Mount Agung, a volcano on the Indonesian island of Bali, has begun spewing volcanic ash. Over 100,000 have been evacuated, but scientists fear that’s only the beginning.

Authorities are warning of the dangerous mudflows now that Mount Agung’s eruption is all but imminent. Since the end of September, the volcano has had people on edge, but many now say they are at least more prepared, as 100,000 flee their homes for safety.

Putu Sulasmi fled with her husband and other family members to a sports hall that is serving as an evacuation center. “We came here on motorcycles. We had to evacuate because our house is just 3 miles from the mountain. We were so scared with the thundering sound and red light,” she told Associated Press. The family had stayed at the same sports center in September and October when the volcano’s alert was at the highest level for several weeks but it didn’t erupt. They had returned to their village about a week ago. “If it has to erupt let it erupt now rather than leaving us in uncertainty. I’ll just accept it if our house is destroyed,” she said.

According to the Guardian, the airport has also been shut down, stranding tourists. Bali is one of Indonesia’s top tourist locations. Airport spokesman Air Ahsanurrohim said 445 flights were canceled, stranding about 59,000 travelers. The closure is in effect until Tuesday morning although officials said the situation would be reviewed every six hours. Instrumental measurement of Mt. Agung began after the last big eruption occurred in 1963, an event that lasted a year and killed more than 1,000 people.

Mount Agung has been spewing volcano ash with increasing intensity since last Tuesday, but after heightened seismic activity and confirmation that the volcano is shifting into the magmatic phase, authorities raised the warning level to the maximum level 4 alert on Monday morning.

Indonesia’s disaster mitigation agency has strongly urged people to immediately evacuate the designated exclusion zone, which has been extended to an 8-10km radius of the volcano. “We ask people in the danger zone to evacuate immediately because there’s a potential for a bigger eruption,” said Sutopo Purwo Nugroho, a spokesman for Indonesia’s disaster mitigation agency (BNPB). Up to 40,000 people had been evacuated but a further 60,000 also needed to move, he said. The governor of Bali said later that 150,000 could be called on to evacuate.

“Not all residents have evacuated yet. There are those (who haven’t evacuated) because their farm animals haven’t been evacuated yet. There are those who feel they are safe,” Sutopo said, adding that security personnel were trying to persuade people to leave. If they refuse to leave their homes, they could be evacuated by force.