Barcelona is in a second day without electricity after a power failure blacked out almost the entire city.

The outage began Monday morning and affected public transport, hospitals, businesses and more than 300,000 homes in Spain's second largest city. Eighty thousand households remain without power and it is not clear when service will be fully restored.

Barcelona's mayor, Jordi Hereu, called the situation unacceptable. Local businesses accused the city's electricity companies, Fecsa-Endesa and Red Electrica de Espana, of not investing enough in Spain's Catalonia region, of which Barcelona is the capital.

City officials said Tuesday that some traffic lights are still not functioning.

A broken cable caused the blackout, which snarled traffic, darkened stores and homes, and trapped thousands in subways and elevators. Hospitals relied on emergency generators, but reported no serious injuries. Barcelona's airport was not affected.

Some information for this report was provided by AP and Reuters.