As per the Japan Meteorological Agency (JMA), a 3.8 magnitude earthquake was reported at approximately 1512 hours (local time) on Wednesday (20 May), with its epicentre located off the coast of Fukushima Prefecture.

The earthquake occurred at a depth of approximately 70 kilometres. Seismic intensity level one was recorded in Iwanuma City in Miyagi Prefecture, and in Tamura City and Hirono Town in Fukushima Prefecture.