A three-point-five magnitude aftershock rattled the Gyeongju area at 11:53 a.m. Wednesday.
No immediate casualties and property damage have been reported.
Its epicenter was found to be located one-point-two kilometers north from a spot that saw a four-point-five magnitude aftershock on Monday.
The KTX high-speed railway passes 600 meters east from the epicenter and six-point-three kilometers northwest is Singyeongju Station, which serves the Gyeongju area. One-point-four kilometers east from the epicenter is the Gyeongbu Expressway which links Seoul and Busan.
The epicenter is also six-point-three kilometers south-southwest from the epicenter of the five-point-eight magnitude quake that jolted Gyeongju on September 12th.