Millions of people in Spain, Portugal and parts of southern France lost power on Monday following a "severe disruption" in the European electrical system, the Spanish prime minister said. The cause of the disruption is still unknown,

Spain and Portugal are reeling from a massive, unexplained power outage that knocked out traffic lights, caused chaos on roads and in airports, and prompted both countries to declare a state of emergency.

A massive power cut hit large parts of Spain and Portugal on Monday, causing widespread chaos and disruption. The outage left millions of people without electricity, while internet and phone networks were also down. Trains were cancelled and evacuated in some regions, traffic lights stopped working amid mounting delays at airports.