Thousands of people are fleeing an erupting volcano on the densely populated Indonesian island of Java. Last time the Merapi volcano erupted some 12 years ago, over 60 people were killed. The government has declared a red alert and put emergency plans into action.The 3000-metre high mountain is about 400km east of the capital, Jakarta. It is one of at least 120 active volcanoes in Indonesia. Thick smoke is rising from the crater and lava is spreading around the mountain. Roads leading from the area are filled with families, some with their livestock, who are being evacuated from the danger zone.