Fire department rescue teams in Chengdu, southwest China's Sichuan Province, were immediately placed on standby and prepared for rapid deployment following earthquakes on July 5, 2026. (Photo: VCG)
Three earthquakes of magnitudes of 4.0 and above struck Mianzhu, a county-level city in Deyang, Southwest China's Sichuan Province, within half an hour late on Sunday night, according to official sources including China Earthquake Networks Center and the Sichuan Provincial Department of Emergency Management. Emergency response forces were swiftly mobilized following the tremors, and no casualties have been reported so far.
According to official measurements, three earthquakes struck Mianzhu at 11:03 pm, 11:20 pm and 11:30 pm on Sunday, one of magnitude-4.5 at the depth of 20 kilometers, one of magnitude-4.0 at 15 kilometers, and one of magnitude-4.5 at 18 km.
The earthquake relief headquarters at provincial, city and county levels activated emergency response and began damage assessments immediately after the quakes. No casualties or damage to buildings have been reported so far, and there have been no reports of damage to transportation, power, or telecommunications infrastructure. Local authorities are continuing further inspections in the epicenter and surrounding areas.
The recent earthquakes are considered aftershocks of the 2008 Wenchuan earthquake. In response to public concerns over why aftershocks can still occur 18 years after the main shock, senior engineer Qi Yuping from the Sichuan Earthquake Administration explained that after a major earthquake, crustal stress in the affected region is released gradually over a long period of time, according to China National Radio (CNR), citing information provided by the Sichuan Earthquake Administration.
As a result, the overall intensity and frequency of seismic activity decline over time, but periodic fluctuations in earthquake activity are a normal geological process. Long-term aftershocks are a common phenomenon following major earthquakes, she added, CNR reported.
The magnitude-8.0 Wenchuan earthquake struck Southwest China's Sichuan Province on May 12, 2008, taking nearly 70,000 lives and leaving about 18,000 missing, according to the Xinhua News Agency.
Zhou Weidong, a natural disaster and earthquake research expert, told the Global Times on Monday that the recent earthquakes in Mianzhu can be described as an "earthquake swarm," noting that multiple relatively strong quakes occurred in a short period rather than a single clearly dominant main shock. He also said that these series of earthquakes are a part of the late aftershock sequence of the 2008 Wenchuan magnitude-8.0 earthquake.
Zhou added that Sichuan sits at the boundary of tectonic plates with active fault lines and complex geological conditions, where stress can accumulate and be released more frequently, making earthquake activity relatively common in the region.