On 28 July 2026 at approximately 16:27:15 JST (07:27:15 UTC), an earthquake struck Kumamoto Prefecture in southern Japan with a magnitude of () at a depth of , later revised to . At least 38 people were killed and more than 368 were injured.

The Japan Meteorological Agency (JMA) has officially named the earthquake the .

Earthquake

The earthquake occurred at 16:27 JST (07:27 UTC) on 28 July in Kumamoto Prefecture, Japan. According to the Japan Meteorological Agency (JMA), the earthquake had a magnitude of . The United States Geological Survey (USGS) recorded an earthquake of with an epicenter west-southwest of the city of Uki. It was caused by strike‑slip faulting. The USGS focal mechanism solution suggested coseismic slip occurred on either a northwest-trending left‑lateral fault or a northeast-trending right‑lateral fault.

Geology Kumamoto Prefecture is located on Kyushu, the most southerly of Japan's four main islands. It lies at the southern end of the Japan Median Tectonic Line, Japan's longest, where a system of active faults forks in two directions at the Beppu-Haneyama fault zone. Earthquakes occur along the Beppu–Shimabara graben, with epicenters moving from west to east over time. To the southeast of Kumamoto, the continuation of the Japan Median Tectonic Line is the major southwest–northeast trending strike-slip Futagawa-Hinagu fault zone system, consisting of the Futugawa fault to the north and the Hinagu fault to the south, parts of which ruptured during the 2016 Kumamoto earthquakes.

The Hinagu fault is long and can be divided into three segments; Takano-Shiraha, Hinagu and Yatsushiro. According to Shinji Tōda, a scientist at Tohoku University, the earthquake was caused by slip on a section of the northeastern Hinagu segment. Tōda added that while the rupture relieved seismic strain on that segment, it loaded additional strain on adjacent ones. The Takano-Shirahata segment was previously involved in the 2016 Kumamoto earthquakes, hence the likelihood of another rupture on this segment remained low. However, the Yatsushiro and southwestern Hinagu segments which lie further south and also in the Yatsushiro Sea have a greater probability of rupturing, capable of producing a event and tsunami.

Similarly, the 2016 earthquakes which occurred on the northern segment of the Hinagu fault likely increased stress on its southern segments. The 2016 earthquakes caused of slip on the northern Hinagu fault while during the 2026 earthquake, it produced slip. Prior to 2026, the Hinagu fault was identified as a potential source of large earthquakes. A national seismic hazard assessment report published in January 2026 identified the Hinagu segment as having a 6% probability of rupturing within the next 30 years; the greatest probability among all faults in the country.

The USGS modelled an earthquake with slip across a long northeast-trending fault, extending down to depth. According to the model, the rupture propagated bilaterally, extending northeast and southwest from the epicenter and was completed in about 18 seconds. Slip extended about northeast of the epicenter and southwest, although most was confined to a area on the fault plane immediately southwest of the epicenter. A maximum slip of was inferred at a depth of about in this region of large slip beneath Uki. Towards the surface, the displacement was limited, ranging from negligible to about along most of its length while peaking at at the shallowest portion of the main slip patch.

Seismic intensity A maximum intensity of 7 on the Japan Meteorological Agency seismic intensity scale was recorded in Uki and Hikawa, the highest on the scale. Intensity 6+ was recorded in Minami-ku, Yatsushiro, Uto, Misato, and Mashiki. Aftershocks up to intensity 5- on the JMA seismic intensity scale were also felt. According to the USGS, a seismic station in Mashiki recorded a peak ground acceleration of 0.705 g, while another station in Yatsushiro recorded a peak ground velocity of /s. Japan's strong-motion seismograph network recorded a peak acceleration value of about 1.7 g. The Japan Meteorological Agency and Earthquake Research Headquarters said it recorded a peak ground acceleration of 2,437 gal (2.49 g) in Toyono, Uki; this value exceeds the maximum recorded acceleration of 1,791 gal during the 2016 earthquake.

Tremors were also felt in parts of South Korea, with more than 789 reports of the tremor being received, including 291 in Busan alone. The Korea Meteorological Administration reported a Modified Mercalli intensity of III (Weak) in Busan, South Gyeongsang Province, South Jeolla Province, Gwangju, and Jeju Province. Intensity II (Weak) was observed in Gangwon, Gyeonggi, North Gyeongsang Province, Daegu, Ulsan, North Jeolla Province, South Chungcheong Province, and North Chungcheong Province. In China, residents in Shanghai said they felt tremors, while multiple people in Ningbo and Suzhou reported feeling disoriented.

+Locations with a seismic intensity of Shindo 5− and higherIntensityPrefectureLocations7KumamotoUki, Hikawa6+ KumamotoKumamoto City (Minami-ku), Yatsushiro, Uto, Misato, Mashiki6− KumamotoKoshi, Ōzu, Nishihara, Mifune, Kamiamakusa, Ashikita 5+ KumamotoKumamoto City (Chūō, Higashi, Nishi, Kita), Yamaga, Kikuchi, Kikuyō, Minamata, Amakusa, Tsunagi NagasakiMinamishimabaraKagoshimaSatsumasendai, Satsuma, Nagashima5− KumamotoTamana, Nagomi, Yamato, Reihoku, Aso, Takamori, Minamiaso, Hitoyoshi, Taragi, Yunomae, Yamae, Asagiri NagasakiUnzen, IsahayaKagoshimaAkune, Izumi, Ichikikushikino, Isa, Yusui SagaKanzaki, ShiroishiFukuokaYanagawa, OkawaMiyazakiNobeoka, Saito, Shiiba

Long-period ground motion The also reported that the Kumamoto Region of Kumamoto Prefecture registered the highest possible Long-Period Ground Motion (LPGM) intensity of 4. +Locations with Class of II or higher observedClass PrefectureLocationsIVKumamotoKumamoto RegionIIIKumamotoAmakusa and AshikitaIIKumamotoAso Region, Kuma RegionOitaWestern OitaMiyazakiSouthern Miyazaki Mountains, Northern Miyazaki PlainsKagoshimaSatsuma RegionSagaSouthern Saga

Aftershocks

At least 390 aftershocks were recorded following the earthquake. The JMA warned of the possible occurrence of earthquakes with a maximum seismic intensity of 7 for the next two to three days following the initial tremor.

A list of major earthquakes that occurred in the vicinity of the epicenter following the mainshock (including the mainshock itself).

+ Date and time of occurrence (JST) Epicenter Depth of the earthquake's hypocenter Magnitude Maximum seismic intensity Maximum class of long-period ground motion 16:27, July 28, 2026Kumamoto Region, Kumamoto Prefecture16 kmM 7.1 7IV16:29, July 28, 2026Kumamoto Region, Kumamoto PrefectureVery shallowM 4.5 5−II17:08, July 28, 2026Amakusa and Ashikita regions, Kumamoto PrefectureVery shallowM 6.15−II19:03, July 28, 2026Kumamoto Region, Kumamoto Prefecture10 kmM 4.25−No observations22:19, July 29, 2026Amakusa and Ashikita regions, Kumamoto PrefectureVery shallowM 5.85−I21:47, August 1, 2026Kumamoto Region, Kumamoto Prefecture10 kmM 4.75−No observations

Ground effects

Ground deformation was reported by the Geospatial Information Authority of Japan. In Yatsushiro, the Sencho geographic reference point was displaced northeast, and the Izumi station recorded a shift southward. In Kumamoto, the Jonan station recorded of displacement to the north. Surface ruptures were also reported on the ground surface caused by fault slip. The earthquake also caused soil liquefaction in Kumamoto, where the ground is characterised by loose sediment and a shallow water table. It caused roads to twist and tilted homes.

Slip towards the ground surface along the Hinagu Fault caused ruptures that damaged overlying infrastructure such as roads, bridges, and buildings. Satellite imagery analysis by NHK revealed of visible surface rupturing between Hikawa and Yatsushiro. Geologist Shinji Toda from Tohoku University said these ruptures only represented where the rupture breached the surface; for a significant portion of its length, the rupture did not reach the surface. An inference of crustal deformation data suggests a rupture length closer to . At Takaki, Mifune, surface ruptures were also reported after the 2016 earthquakes. In Ogawa, Uki, fault slip caused vertical ground displacement through an urbanized area. A surface rupture propagated under a viaduct near the junction of the Kyushu Expressway and Minamikyushu Expressways, breaking along a column and causing one side to drop vertically. At a parking lot in Mifune, the ground shifted laterally to the right by and caused a bulge.

Impact

Officials from Kumamoto Prefecture said that 38 deaths were recorded. Some deaths were indirect such as the case of a woman found inside a car on 30 July who died in her sleep from heat stroke which authorities said was disaster-related. Among the dead were 20 in Yatsushiro, 7 in Kashima, 5 in Hikawa, 3 in Uki and 1 in Kōsa. A total of 358 people were injured; 364 in Kumamoto, two in Fukuoka, and one each in Kagoshima and Ōita prefectures. At least 34 of those injured were in serious condition. Across Kyushu, 31,951 homes sustained damage, including 1,449 which collapsed and 1,185 which were partially destroyed. Around 10,000 people were displaced. Commercial and industrial businesses sustained losses of 117.6 billion yen ($738.2 million).

An estimated 3,000 shoppers were inside the in Kashima when the second floor collapsed, followed by an explosion. Rescuers retrieved seven bodies and five survivors from the wreckage. A person inside a pub from the mall said he heard an explosion after the earthquake and saw a large cloud of smoke rising above the building. About 55 people were injured in the blast. The cause of the explosion was not known, although a government official told the press that there were reports of a gas leak. The industry ministry later said that the explosion was likely caused by liquefied petroleum gas used by the mall's restaurants for cooking and heating water following an on-site investigation. The earthquake prompted an evacuation of the shoppers; after that, some employees of the mall returned inside and were later caught in the blast. Two of the dead were employees of the variety store chain Habita who had initially evacuated following the earthquake but were ordered by the sales manager to return and transfer money stored in the cash register to a safe. The company subsequently apologized over the incident.

In Yatsushiro, the chimney of a factory owned by Nippon Paper Industries collapsed, killing nine people and injuring two. Another person was killed by a collapsed house in the city. The worship hall of the 19th-century Yatsushiro-gū shrine and a section of a bridge also collapsed and fires were reported in the city and in Matsubase. Two residents and a staff member at a nursing home in Hikawa were injured by a collapsed wall. One Vietnamese national died after a crane collapsed on him in Kōsa, and another was injured after a wall collapsed.

At least 179 homes collapsed, and 1,269 others were damaged. All of the damaged houses were in Kumamoto Prefecture, with the exception of eight partially damaged houses in Fukuoka Prefecture. In Hikawa, at least 125 homes and buildings collapsed, and 754 others were damaged. In Uki, parts of the ceiling at also collapsed, and one person was found dead under a collapsed wall. Five people were initially trapped after two houses collapsed in the city. According to JR Kyushu, a freight train derailed near Yatsushiro Station. At least 12 people sustained arm or leg bruises inside a Kyushu Shinkansen train near Shin-Yatsushiro Station. The agency said there were more than 200 reports of snapped rails and collapsed sound barriers, but no Shinkansen trains derailed. Bent rails were reported at a train depot in Kumamoto and between Matsubase and Ogawa stations on the Kagoshima Main Line.