Many countries experienced a massive power outage on April 28.

Portgual and Spain are under a state of emergency.

At this stage, theres no evidence yet regarding the cause of the massive blackout.

Aerial view of a city intersection with historic buildings in Madrid, Spain

Downtown Madrid, Spain, where the Calle de Alcala meets the Gran Via.Credit:Pol Albarrán/Getty Images

A cyberattack has not been ruled out, and investigations are ongoing."

Lisbon’s Humberto Delgado Airport are reportedly not accepting arrival flights through at least 3:30 pm GMT.

The airport in Lisbon has also reportedly been affected.

This is a developing story.