The eruption of Papua New Guinea's tallest volcano has subsided but thick ash meant flights have been cancelled

One of the South Pacific nation’s most active volcanoes, Mount Ulawun erupted on Monday afternoon, spewing ash as high as 9.3 miles (15km). The alert level for the volcano was downgraded from Stage 4, 'very strong eruption', to stage 3, 'moderate-to-strong eruption'.