That conclusion has been supported by the operator of Spain’s national grid, Red Eléctrica, which has located where outages began on Monday. Two separate incidents of power outages led to instability in the grid leading to a “breakdown in interconnections with France,” leaving the Iberian grid isolated.

A massive power outage has knocked out electricity across parts of Spain and Portugal, shutting off traffic lights and causing chaos at airports, train stations and on the roads. Follow for live updates.