The warning issued by the Volcanology and Geological Disaster Mitigation Center of the Ministry of Energy and Mineral Resources in Bandung was the highest level alert possible, ANTARA reported.

"We are still strongly advising tourists not to climb Mount Anak Krakatau," the official Indonesian news agency quoted the head of the center as saying. "We have also established coordination with the managers of tourist facilities, like hotels, in the area in warning guests not to ascend the mountain at all."