Japanese authorities announced that "a 6.3 magnitude earthquake struck the Ishikawa region in the west of the country today, Friday," warning of aftershocks without issuing a tsunami warning. The Japan Broadcasting Corporation (NHK) reported that "no tsunami warning was issued after the earthquake." The earthquake resulted in injuries and the collapse of buildings in the area. Both NTV and Kyodo News reported that "no abnormal conditions were reported at the Shika nuclear power plant in the Ishikawa region, nor at the Kashiwazaki-Kariwa plant in the nearby Niigata Prefecture." Chief Cabinet Secretary Hirokazu Matsuno stated in an emergency press conference that "a person suffered a heart attack after the earthquake, without providing further details." A meteorological agency official noted that "large earthquakes could occur, especially in the next three days," adding that "aftershocks have already followed the earthquake." Residents in the affected areas were urged to exercise caution for about a week in anticipation of further tremors. A Japanese citizen commented on Twitter: "The severe shaking threw us to the ground, and we lost our balance."