Did Israel strikes trigger earthquake in Tehran? Tremors could be linked to Iran nuclear testing - what analysts say

A 5.1-magnitude earthquake struck northern Iran on Friday, according to the United States Geological Survey (USGS), as Israel continued its barrage of airstrikes on Iranian targets.

While Iran’s official news agency IRNA reported no casualties and described the damage as “minimal,” the tremor has sparked international speculation about its possible connection to Iran’s controversial nuclear program.

The quake, which the USGS said originated at a depth of 10 kilometers (six miles), was centred approximately 37 kilometres (23 miles) southwest of Semnan city.

However, Iran’s state television reported a stronger magnitude of 5.5, stating that the epicentre was near the city of Sorkheh in Semnan province . The tremor was reportedly felt in the capital, Tehran, located about 150 kilometres (90 miles) from the affected area.

Nuclear test suspicions

Amid the heightened military tensions with Israel, some analysts have raised the possibility that the seismic activity could be linked to underground nuclear testing by Iran -- a claim that remains unverified. The timing of the quake, coinciding with ongoing Israeli airstrikes , has fueled speculation on social media and among regional security observers.

Semnan province holds particular significance in Iran’s nuclear and missile infrastructure. The region is home to the Semnan Space Centre, a key launch site for Iran’s satellite and ballistic missile programs, and lies relatively close to the Fordow and Natanz nuclear facilities, both central to Iran’s uranium enrichment efforts.

While Iran has consistently denied pursuing nuclear weapons, international scrutiny intensified after the collapse of the 2015 Joint Comprehensive Plan of Action (JCPOA) following the United States' unilateral withdrawal in 2018.

A history of nuclear tension

Iran’s nuclear ambitions date back to the 1950s under the US-backed "Atoms for Peace" program but have evolved into one of the West Asia’s most contentious geopolitical flashpoints. Western nations, particularly the United States and Israel, have long accused Tehran of seeking nuclear weapons capability under the guise of a civilian program -- a claim Iran firmly rejects.

The region's complex seismology, combined with Iran’s history of secretive nuclear development, has often triggered speculation whenever earthquakes occur near sensitive sites. However, experts caution that Iran is naturally prone to seismic activity, given its location on major fault lines.

Geopolitical implications

If verified, any link between seismic events and potential nuclear testing would dramatically escalate tensions, not just between Israel and Iran but also across the broader West Asia. It would likely trigger calls for new sanctions and increase pressure on international bodies like the International Atomic Energy Agency (IAEA) to launch immediate investigations.

For now, both Iranian officials and the global scientific community continue to attribute Friday’s earthquake to natural tectonic activity. Still, in a region already on edge, the tremor has added another layer of uncertainty to an already volatile situation.