A massive power outage is impacting Spain and Portugal, knocking out key services and forcing the evacuation of subway systems in both countries, reports say.

A massive power outage appears to have affected large portions of Spain and Portugal Monday. Red Electrica, the operator of Spain's power grid, said on social media Monday morning that voltage has been recovered in substations in several areas in the north,

Officials are investigating the cause of the outages, while smaller blackouts were also reported in France and Andorra.