Authorities warned thousands of people on Lembata Island, East Nusa Tenggara (NTT) to prepare to evacuate after a volcano started spewing rocks and lava. The 748-metre Batutara volcano , which began rumbling last week, released hot lava and rocks over the last two days and shot clouds of hot air as high as 2,000 metres. Andreas Duli Manuk, chief of Lembata district, said about 6,800 residents in six villages on the northern coast of Lembata island, the closest islet south of the volcano, were on alert for evacuation. He added some have already fled their villages to safer areas.