JAKARTA; A volcano in Indonesia’s eastern island of Halmahera erupted on Saturday, spewing a 5km-high ash cloud, the country’s volcanology agency (PVMBG) said, while its disaster agency warned of potential flash floods and cold lava flow.

The eruption of Mount Ibu at 11.03am local time follows a series of eruptions in May, after authorities noticed an uptick of volcanic activity starting in April, leading to the evacuation of seven nearby villages.

“The ash column is grey with thick intensity and leaning towards the southwest,” the agency said, adding that residents and tourists should maintain a distance of at least 7 km from the active crater.

Footage shared by the agency showed the volcano spewing ash that grew thicker and eventually dispersed.

Indonesia’s disaster management agency BNPB told local authorities to anticipate secondary disasters such as flash floods and cold lava flow. Analysis by the nation’s meteorology agency shows the region has the potential for moderate to heavy rain, although it did not say when.

“If there is a buildup of material left over from the eruption, it should be cleaned up immediately because it is dangerous. If there is heavy rain, flash floods could occur, cause damage and many fatalities,” Suharyanto, the BNPB chief, had said in a statement on Friday.

The volcano has been on PVMBG’s highest alert level since May 16. Mount Ibu’s recent activity follows a series of eruptions of other volcanoes in Indonesia, which sits on the Pacific “Ring of Fire” and has 127 active volcanoes.

Flash floods and cold lava flow from Mount Merapi, one of the most active volcanoes in West Sumatra province, covered several nearby districts following torrential rain on May 11, killing at least 67 people with 20 people still missing.