Activity on the Indonesian volcano Mount Merapi has intensified, with continuous clouds of ash, gas and rock fragments spewing from its crater.
One of the emissions sent a pile of debris 4km (2.5 miles) down one side of the mountain, scientists said.
Experts monitoring the volcano, in central Java, raised its alert status to the highest level on Saturday.
Thousands of people have been moved from the volcano's upper slopes, but a small number are refusing to leave.
So far there have been no confirmed reports of fresh lava flows from Mount Merapi on Monday, but the volcano is becoming more active by the day.
At least one village about 3 km ( 2 miles) from the crater has already been covered in a thin coat of volcanic ash.
Subandriyo, a vulcanologist on Merapi, told the BBC that he now believes the volcano is in the early stages of an eruption, adding that it was not possible to predict "when it will reach its peak".
But the Centre of Vulcanological Research and Technology (CVRT) in Yogyakarta - an historic university town about 25 miles (40 km) from Mount Merapi - said that the clouds were not necessarily a sign that the volcano was erupting.
"It is only a sign of extraordinary activity," said Jilal, a CVRT official.
By Sunday more than 4,500 people living in the villages closest to the crater, or next to rivers that could provide channels for hot lava, had been moved to emergency shelters.
Many more are still lining up by the side of the road, waiting for trucks to take them to safety.
But there are still a few farmers refusing to move. Without their crops and animals, they have no income and cannot support their families, so they are waiting until the government offers financial help.
Others - mainly fathers and their sons - are spending nights outside the danger zone but are travelling back during the day to tend to farms and livestock.
The mountain is also revered by many locals, who believe mystical sprits live in the volcano's crater. Many say they are waiting for specific signs - such as clouds in the shape of a sheep's fleece - to show them an eruption is imminent.
'MOUNTAIN OF FIRE'
Merapi has had 68 historic eruptions since 1548
In 1994 a gas cloud burned 60 people to death
About 1,300 died when it erupted in 1930
Most violent eruption in recent history was in 1872
Major eruption in 1006 covered all of central Java with ash
Merapi, which means "mountain of fire", is one of the most fearsome volcanoes in the Pacific "Ring of Fire".
A gas cloud from the volcano's last eruption in 1994 killed 60 people.
One of its deadliest eruptions was in 1930, when about 1,300 people were killed.
I am working in Solo with an International NGO and we are now making preparations for evacuation in case of a big eruption. My main concern is the ash that could fall in a large area around Merapi. I have three young children here with me and the ash is known to cause more problems for children, than adults. We are taking what precautions we can and stocking up on food and drinking water, in case we get caught and have to stay indoors for several days. I am sure we are far enough away to be affected too badly but if it does blow we will try to travel to a farther away city, like Surabaya.
Jack O'Kane, Solo, Indonesia
I have been living in Yogyakarta for 4 years now and am located near Gadjah Mada University (around 40Km from Merapi - if I'm not mistaken). Merapi is just like a friend to people living in Yogyakarta, especially to us, university students who are fond of hiking and climbing.
10 days ago I went to the Cangkringan Resort which is very close to the Merapi top, but the situation that time was different from what it is like now. Some villagers and the staff at the Cangkringan felt disappointed and complained about the media which seemed to exaggerate the news on Merapi that caused the decreasing in tourist visits. Well, I couldn't disagree with them that time. The situation seemed fine and not as bad as what it reported on TV or newspapers.
But now, the situation is really different from 10 days ago. I do believe in what the news and government have reported. Besides, since 3 days ago I have watched some volcanic ash spew from Merapi top and it's clearly seen from my place in the mornings. The lava can also be seen at nights. About 1 hour ago I was watching the glowing lava ooze down its side...
I do hope the villagers who live close to Merapi are willing to be evacuated and not think of their possessions this time.
If the eruption will be huge, the Yogyakarta city may be covered by big black ash. Hope no one will be a victim and no one takes advantage of this Merapi situation (such as pretending to ask for donation to help the needy people living near Merapi).
Dewi, Yogyakarta, Indonesia
I climbed Merapi in 1994 a month before the previous eruption which killed a number of local inhabitants. Standing at the peak of Merapi and looking out over Central Java is an awe inspiring occasion and it is not hard to believe the respect and affection that local inhabitants, who live and work on the mountains slopes, have for this volcano. Many cultivate crops quite close to the cone section, and it is not hard to understand their reluctance to leave their homes.
Terry Gray, Balikpapan, Indonesia
I have just arrived in Jogjakarta, flying in we had an amazing view of Merapi, with a large plume of smoke billowing from it, it was an amazing sight! I'll be looking out for the lava flow tonight.
John Reynolds, London, UK
I visited mount Merapi several times before the eruption, I have the impression that the future serious suffering of the people in the surrounding will be due to the lowering of the subsoil water table, particularly for the people who live from agriculture. During my visits to the area I noted that a large number of water springs are drying! I use to visits motivates local members who are interested with the effort of conserving the remaining forest on the slope of Merapi from Turen, Cangkringan to Klawung forestrial area, in the Yogyakarta Sleman district.
Boedhihartono, Depok UI-campus, Jakarta
I was born in a village about 10 km east from Merapi. Now I live in Cilegon, near the volcano of Krakatau in Banten. I have climbed Merapi twice. The villagers around Mount Merapi have a strong believe in whatever the keeper of Merapi Mr. Marijan says. He is the one, who can see the condition of the volcano from the mystical side. If Mr. Marijan does not leave the mountain, the villagers won't leave either. Most of them are not well educated and believe in superstitions.
Rochedi Zuwono, Indonesia
I have friends in Indonesia and I know that the evacuation is not good. I've seen migration from homeland to kenya and faced many problem. Human life is much more important than the life stock because life stock is replaceable but human life is not replaceable. On the other hand the soil will become much more fertile after the eruption. This is why volcano eruptions are important.
Geele Farah, Kenya
Mt Merapi certainly seems to exhibit clear signs of an imminent eruption. The scale of the potential disaster depends on the location of the local communities. They thrive within these areas because of the fertile soil secured by regular eruptions. However it is the increased density of the population that draws more concern for the potential hazard. It is not surprising that many farmers are reluctant to leave their land given that there is no compensatory package provided by the government. The risk to human lifes is becoming ever greater, and the socioeconomic infrastructure is under serious threat. The power of nature cannot be undermined, that is always the case in areas prone to geophysical hazards.....You've got to learn to live with the hazard, but the disaster can be significantly reduced by appropriate preparedness - something the Indonesians seem to have achieved, at least in part.
Chris Brodie, Denny
I was born and lived for 7 years in the District of Magelang, where half of Gunung Merapi is located. I still remember every time I went back from school, I faced Merapi. Every time I heard that Merapi is going to explode, I often heard the terrible news from people, and also heard the myths connected with it. Can't imagine the condition now. I also visited Merapi, but I did not climb, and remember there were a lot of houses. I often wondered what will happen to them.
William Tanoto, UK
I visited Merapi in 1994. What concerned me most was that the city of Jogjakarta has a population of over 10 million people. If Merapi was to erupt on a massive scale this could be one of the worlds greatest humanitarian disasters.
Tim Butler, UK
I have friends in Indonesia and wish everyone is more willing to leave since the eruption is very dangerous and death is imminent. don't worry about life stock because they are replaceable but your life can't. The soil in the farmland will become much more fertile after the eruption.
Sherwin Lo, Marietta, USA
I live 35 km to the east of mount Merapi. Luckily for me, the eruption never affect areas in the east of Merapi but only to the north and northwest. After the eruption, the sky will be very dark and it will rain of ash and dirt for about two hours. When I was a kid, the eruption didn't affect us directly but the whole town was covered by thick-gray-ash and we spent hours to sweep it off our roof and garden. Yesterday I heard that some poor farmers wanted the government to buy their cattle and livestock because it is the only possession they have. It's an old old story, EVERY TIME Merapi erupts, there are ALWAYS dead victims. Usually it's the ones who decided to stay in the Merapi's vicinity.
Winarto, Solo, Indonesia
I am a Canadian who used to live in Yogyakarta 20 years ago. I fell in love with the people, the land and climbed Merapi. It was common to leave at dusk in order to watch the sunrise from the peak of Merapi. I stay in touch with my friends there who are nervous - remember this if from the land of Krakatoa and one only needs to think of Pompeii to realise what could happen.
Spencer Campbell, Canada