<P> Many of the Aetas who lived on the slopes of the volcano left their villages of their own volition when the first blasts began in April, gathering in a village about 12 kilometres (7.5 mi) from the summit . They moved to increasingly distant settlements as the eruptions escalated, some Aetas moving up to nine times in the two months before the colossal eruption . </P> <P> The first formal evacuations were ordered for the 10 km (6.2 mi) zone on April 7 . Evacuation of the 10--20 km (6.2--12.4 mi) zone was ordered when a level 4 alert was issued on June 7 . A level 5 alert triggered evacuation of the 20--40 km (12--25 mi) zone on June 13, and in all some 60,000 people had left the area within 30 kilometres (19 mi) of the volcano before June 15 . Most people temporarily relocated to Metro Manila, with some 30,000 using the Amoranto Velodrome in Quezon City as an evacuee camp . </P> <Table> <Tr> <Th_colspan="2"> 1991 Mount Pinatubo eruption </Th> </Tr> <Tr> <Td_colspan="2"> The eruption cloud shortly before the colossal climactic eruption . </Td> </Tr> <Tr> <Th> Date </Th> <Td> June 15, 1991 </Td> </Tr> <Tr> <Th> Type </Th> <Td> Ultra-Plinian </Td> </Tr> <Tr> <Th> Location </Th> <Td> Central Luzon Region, Luzon, Philippines </Td> </Tr> <Tr> <Th> VEI </Th> <Td> 6 </Td> </Tr> <Tr> <Th> Impact </Th> <Td> <Ul> <Li> About 20,000 people evacuated </Li> <Li> Approximately 800 people were killed and 10,000 people left homeless </Li> <Li> Huge destruction left in surrounding areas </Li> <Li> Release of 17 megatons of sulfur dioxide into the atmosphere, causing global cooling by 0.5 ° C (0.9 ° F) between 1991--1993 </Li> </Ul> </Td> </Tr> </Table> <Tr> <Th_colspan="2"> 1991 Mount Pinatubo eruption </Th> </Tr>

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