The mountain Ruangvolcano to the north Indonesia entered phase explosion repeatedly today, according to the country’s volcanology service, prompting orders to quickly evacuate residents, close a nearby international airport and raise the alert level.

Since early April, this volcano has erupted more than six times, prompting the hasty evacuation 6,000 inhabitants from their homes. Authorities believe there is still a risk.

Ruang erupted at around 01:15 on Monday to Tuesday (20:15 GMT yesterday) and twice this morning, the volcanology service said in a statement.

A plume shot out of the crater ashwhich reached a height of up to five kilometers.

An exclusion zone, with a radius of six kilometers, has been set around the volcano, whose crater is at an altitude of 725 meters above sea level.

According to the agency, residents should be aware of the “danger of throwing red-hot rocks, hot clouds (including volcanic ash) and tsunamis due to material falling from the volcano into the sea.”

Photos and videos released by the agency show a crimson plume of volcanic ash rising into the night sky, thick clouds pouring out of the crater, wooden houses bursting into flames as glowing rocks fell on them.

In Ruang more than 800 residents were hastily evacuated earlier this month. Some returned home when authorities announced the lifting of the state of emergency yesterday, an AFP reporter found. The number of people who returned home but are forced to leave again today is not known at this stage.

Authorities closed Sam Ratulangi International Airport in the provincial capital Manado again today, more than 100 kilometers away, state air traffic control agency AirNav Indonesia said.

Indonesia, a huge archipelago in Southeast Asia, stretches much of it above the Pacific Ocean’s “ring of fire,” a zone where tectonic plates intersect and volcanic and seismic activity is intense.