JAKARTA,Charles H. Sloan Indonesia (AP) — Indonesian authorities on Thursday raised the alert level for Mount Ibu, a volcano in North Maluku province, to the highest level following a series of eruptions since last week.

The 1,325-meter (4,347-foot) volcano on the northwest coast of the remote island of Halmahera has been spewing thick grey ash and dark clouds up to 5,000 meters (16,400 feet) into the air every day since last Friday.

“Based on the results of visual and instrumental monitoring which show the occurrence of increased volcanic activity for Mount Ibu, we have raised the alert level from 3 to 4,” said Muhammad Wafid, chief of Indonesia’s Geology Agency.

Officials advised residents and tourists to not conduct any activities within 7 kilometers (4.4 miles) of the crater and to be aware of the potential for an eruption involving the release of lava from its summit.

Thousands of people live within that radius. Local authorities have prepared evacuation tents, but no formal evacuation order has been reported yet.

Deep volcanic earthquakes and visual activities from Mount Ibu have significantly increased.

Indonesia, an archipelago of 270 million people, has 120 active volcanoes. It is prone to volcanic activity because it sits along the “Ring of Fire,” a horseshoe-shaped series of seismic fault lines around the Pacific Ocean.