The National Seismological Center of the Institute of Geophysics, University of Tehran, said the strongest earthquake struck at 23:46 local time on May 12 (20:16 UTC), with a reported depth of 10 km (6.2 miles) and epicenter near Pardis.
Iran’s Mehr News Agency reported that the overnight sequence included a total of nine earthquakes in eastern Tehran Province. The shaking was felt in parts of Shemiranat, Pardis, and Damavand. Emergency services and fire stations were placed on readiness status, although authorities reported no confirmed injuries or structural damage.
The earthquakes occurred near the Mosha fault, one of Iran’s main active fault systems, northeast of Tehran. The fault extends approximately 150 km (93 miles) and lies about 40 km (25 miles) from the capital. Tehran is also exposed to several other active structures, including the North Tehran and Rey faults.
Seismologist Mehdi Zare told Mehr News Agency that it remained unclear whether the seismic sequence represented a partial release of accumulated tectonic stress or possible warning activity within the broader fault network affecting the Tehran region.
M4.3 earthquake near Tehran, Iran on May 12, 2026 – Regional seismicity. Credit: EMSC
Tehran’s metropolitan region, with a population exceeding 14 million people, has long been the focus of seismic-risk discussions among Iranian experts because of dense urbanization, infrastructure exposure, transportation congestion, and development near active fault systems.
Iran is among the world’s most seismically active countries due to its position within the Alpine-Himalayan tectonic belt. The country has experienced several destructive earthquakes in recent decades, including the 2003 Bam earthquake, which killed more than 30 000 people.
References:
1 M4.3 earthquake Iran – EMSC – May 12, 2026
2 Strong earthquake strikes Tehran – Mehr News Agency – May 13, 2026
3 Series of tremors near Tehran renew concerns over major quake risk – Reuters – May 13, 2026