BALI, INDONESIA — A week after authorities put Bali’s volcano on high alert, tremors that indicate an eruption is coming show no sign of abating, swelling the exodus from the region to at least 140,000 people.

Disaster authorities on the Indonesian island famed for its lush tropical interior and beguiling beaches said Friday that instruments recorded more than 200 tremors from cone-shaped Mount Agung from dawn until midday.

More than 144,000 people have now left areas around the volcano, including from places outside the immediate danger zone.

Volcanologists say the past week’s dramatic escalation in tremors indicates an eruption is more likely than not, but they can’t say with certainty when it will happen.

The volcano last erupted in 1963, killing more than 1,100 people, and remained active for about a year.

Agency spokesman Sutopo Purwo Nugroho said the chances of an eruption are “quite big”, although experts can’t predict when with certainty.

The people who have fled the volcano are scattered across Bali in more than 400 different locations including temporary camps, sports centres and other public buildings.

The Ministry of Transport says it’s ready to deploy 100 buses to take stranded tourists off Bali if an eruption forces its international airport to close.

The mountain, about 70 kilometres (45 miles) to the northeast of the tourist hotspot of Kuta, is among more than 120 active volcanoes in Indonesia.

Officials say tourists on Bali, which had nearly 5 million visitors last year, are not in danger but they have prepared evacuation plans if an eruption forces the closure of the island’s international airport.

Indonesia, an archipelago 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.