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
Zuidwal volcano Zuidwal volcano The Zuidwal volcano is an extinct volcano in the Netherlands at more than below ground under the Wadden Sea, between Harlingen and Vlieland, just south west of the island Griend. The volcano was last active during the late Jurassic, (about 160 - 148 Ma ago) and has since been covered by about of sedimentary rock, most of it shale and sandstone from the Cretaceous. The volcano was discovered in 1970 when the French oil company Elf Aquitaine was doing test drills in the Wadden Sea, hoping to find a gas field that a seismic survey had indicated. To