The 2006 Hengchun earthquake happened on Tuesday December 26 , 2006 at 12:25 UTC ( 20:25 local time ) near Taiwan . On the surface the center of the earthquake was about 22.8 km west southwest of Hengchun , Pingtung County , Taiwan . The 2006 Hengchun earthquake occurred on Tuesday December 26 , 2006 at 12:25 UTC ( 20:25 local time ) , with an epicenter off the southwest coast of Taiwan , approximately 22.8 km west southwest of Hengchun , Pingtung County , Taiwan , with an exact hypocenter 21.9 km deep in the Luzon Strait , which connects the South China Sea with the Philippine Sea .