Portugal is supplying electricity to clients from its own sources as power exchanges with Spain remain suspended amid an inquiry into the causes of a blackout earlier this week, the energy minister said on Friday.

Electricity is pulsing through Spain and Portugal again after a massive outage knocked out power in both countries on Monday. So too are questions.

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.