Indonesian authorities have raised the state of alertness to the highest level based on fear of an imminent major eruption of Bali's Mount Agung.
The National Board for Disaster Management raised the alert to level four from 06:00 local time (22:00 GMT Sunday), based on the possibility and imminent risk of disaster.
The volcano was seen emitting "continuous ash puffs" occasionally accompanied by "explosive eruptions" and "weak booms" that could be heard 12km (7 miles) from the summit.
Authorities disclosed that dark smoke and ash have been billowing up to 3,400m (11,150ft) above the mountain's peek, which has also been emitting fire.
Residents have been warned by officials to stay clear of rocks and debris, which have been spotted flowing down from the mountain.
The evacuation zone around the volcano has also been widened, while the island's airport has been closed down rendering thousands of tourists stranded.
The main tourist stretch of Kuta and Seminyak is about 70km (43 miles) from the volcano, far beyond the exclusion zone. But the ash made officials to shut down Bali's Ngurah Rai airport from Monday to Tuesday morning
China (statement in Chinese) prompted its citizens to be "cautious" if travelling to Bali.
Officials on Monday disclosed that around 100,000 residents needed to leave, but so far only 40,000 have done so. They have also distributed masks for local residents, as ash rains down in the vicinity.
According to the spokesperson of National Disaster Management Agency Sutopo Purwo Nugroho, the lahars may increase due to heavy rain and as Mount Agung continues to emit pyroclastic material.
Nugroho urged islanders to stay away from lahars as well as avoid activities near rivers.
Authorities have earlier issued warnings of an imminent eruption and raised the alert to the highest level in September after detecting heightened volcanic activity which prompting mass evacuations.
But some islanders returned to their homes in October after the alert level was lowered with a decrease in activity.
