Indonesia raised the alert level for the erupting Anak Krakatau volcano to the second-highest today, and ordered all flights to avoid the area, just days after it triggered a tsunami that killed at least 430 people.   

A crater collapse on the volcanic island at high tide on Saturday sent waves up to 16 feet (5 metres) high smashing into the coast on the Sunda Strait, between the islands of Java and Sumatra.   

Authorities have warned that the crater of Anak Krakatau, or child of Krakatau, remains fragile, raising fears of another collapse and tsunami, and have urged residents to stay away from the coast.   

The volcano has been rumbling on and off since July but has been particularly active since Sunday, spewing lava and rocks, and sending huge clouds of ash up to 3,000 metres into heavily overcast skies.   

The National Geological Agency, in raising the alert level to the second-highest, set a 5km exclusion zone around the island.’All flights 
are rerouted due to Krakatau volcano ash on red alert,’ the government air-traffic control agency AirNav said in a statement.   

Kus Hendratno, a senior official at the Krakatoa observatory, said: ‘We’ve raised the status of [the volcano] since this morning because there’s been a change in the eruption pattern.   
Indonesia, 
(Daily Mail), 27 December 2018 -