An Indonesian volcano saw its biggest eruption in weeks on Sunday, sending huge clouds of ash 3,500 metres (11,500 feet) into the sky, an official said.
"The volcano erupted again this morning, the biggest since late June. It spewed rocks and ash," government vulcanologist Kristianto told AFP.
"We have informed the airport to be on alert as the ash is quite high this time. But so far, flights are not affected yet and the airport is not closed," Kristianto said.
"The volcano is still in eruption phase. We can't predict whether the activity will slow down or if there will more eruptions," he added.
The 1,580-metre Mount Lokon is one of the most active volcanoes in Indonesia. It erupted in 1991, killing a Swiss tourist.
More than 5,200 people have been evacuated to temporary shelters since the volcano erupted on Thursday and its alert status was placed on the highest level, officials said.
The Indonesian archipelago has dozens of active volcanoes and straddles major tectonic fault lines known as the "Ring of Fire" between the Pacific and Indian oceans.
The country's most active volcano, Mount Merapi in central Java, killed more than 350 people in a series of violent eruptions last year.