BUDAPEST, Hungary (AP) — An unprecedented blackout across Spain and Portugal upended the lives of millions across the Iberian Peninsula, a stark reminder of modern society’s reliance on electricity, and how quickly life can descend into chaos when the grid goes down.

The sweeping power outage that hit Spain and Portugal this week has raised questions about the electricity grid in a region not normally known for blackouts.

Spain's investigation into the power outage that blacked out the entire Iberian Peninsula this week continued Thursday as top security officials met Wednesday.