MADRID — The cause of Spain and Portugal’s widespread blackouts remained a mystery on Tuesday, with some isolated disruption remaining after power was largely restored to both countries.

After a nearly daylong power outage upended life for millions across Spain and Portugal, the authorities in both countries are still searching for the cause of the disruption.

Chaos, confusion and cash payments Alanna Gladstone, a 40-year-old film editor, had landed in Portugal’s capital, Lisbon, on a flight from New York hours before the outage.

MADRID, Spain — Power was almost fully restored to Spain and Portugal on Tuesday although many questions remained about what caused one of Europe’s most severe blackouts that grounded flights ...

Power is almost fully restored in Spain and Portugal, although many questions remain about what caused one of Europe’s most severe blackouts.

Power is almost fully restored in Spain and Portugal, although many questions remain about what caused one of Europe’s most severe blackouts.

Power is almost fully restored in Spain and Portugal, although many questions remain about what caused one of Europe’s most severe blackouts.

MADRID (AP) — The cause of Spain and Portugal's widespread blackouts remained a mystery on Tuesday, with some isolated disruption remaining after power was largely restored to both countries ...

The cause of Spain and Portugal’s widespread blackouts remained a mystery on Tuesday, with some isolated disruption remaining after power was largely restored to both countries.

Power returns to Spain and Portugal. The outage’s cause remains a mystery Questions remained about what caused one of Europe’s most severe blackouts.