Jeju uprising to Jeju from Busan and deploying police companies, each 1,700 strong, from the southern provinces of the mainland. The guerrillas retreated to their bases in the forests and caves around Hallasan, an extinct volcano and the highest mountain in South Korea. On April 29, the Korean, non-military, governor of Jeju province abandoned his post, defected, and joined the guerrillas. This caused many police officers, disillusioned by the atrocities they were ordered to commit against their own, to do the same. In response, U.S. military provincial governor William F. Dean ordered a purge of SKLP sympathizers from the ranks of the
Irazú Volcano volcano is contained within the Irazú Volcano National Park, which spreads across 5,705 acres (2,300 ha). The national park contains both primary and secondary montane forests and is home to armadillos, owls, rabbits, foxes, woodpeckers, and hummingbirds. The irazu volcano is a complex volcanic shield. It is the highest active volcano in Costa Rica, and has an area of . It has an irregular subconic shape, and temperatures at its summit vary between , with a record low of -6 °C(21.2 °F) and a record high of 23 °C(73.4 °F). Irazu volcano is a stratovolcano with a summit elevation of