Indonesia has closed seven airports as the Mount Kelud volcano in East Java remains on top alert after its eruption Thursday night, though tens of thousands of evacuees have returned home, an official said here Saturday. Three people have been dead after powerful burst of ash, gravel and sands were shot as high as 17,000 meters, while about 23,860 displaced persons have came back to their homes, said Sutopo Purwo Nugroho, spokesman of the national disaster agency. There are 76,388 people living in shelters at present, he said. Fears of potential hot ashes still linger within the dangerous zone of 10 km from the crater, Head of the Geology Agency Surono said on Friday. "Seven airports have been closed, and now, despite there are no outpours of rain of ash and sands, the environment of the airports are still covered by sand and ash, so the operations remain stopped," Sutopo told Xinhua via the phone. All the air transport facilities are located in the provinces of East Java, Central Java, Yogyakarta and West Java, according to Sutopo. According to the report of the Washington-based Volcanic Ash Advisory Center (VAAC) for Indonesian region on Saturday, most of the volcanic ash has left Sumatra and Java islands and is heading eastward to western Sumatra. "The VAAC recommends planes to re-route pathway on that area," said Sutopo. On Friday, the Indonesian transport ministry issued a warning on flight to avoid routes near the Kelud volcano. Sutopo said more than 2,500 soldiers and police personnel have been mobilized to help cleaning the ash. The last volcanic eruption of Mount Kelud occurred in 2007 and its strongest eruption took place in 1919 claiming 55 lives. Indonesia has just endured a months-long volcanic eruption of Mount Sinabung in North Sumatra that killed 17 people. Mount Kelud is among 129 active volcanoes in Indonesia, which is prone to seismic upheaval as it lies on the Pacific "Ring of Fire," an arc of volcano and fault lines surrounding the Pacific Basin.