Hundreds of people got stuck in lifts while switched-off traffic lights snarled up roads across Italy yesterday as heavy demand caused by a heatwave forced electricity companies to cut back on power.

The national grid operator had to order the cut - which amounted to about 5% of national demand - to stave off a huge blackout.

Italians had turned on their air conditioning and pumped up their fridges as temperatures soared above 30C.

Power cuts occurred in cities across the country, from Trieste in the northeast to Naples in the south and Palermo in Sicily.

In Rome, where 350,000 users were left without electricity, police struggled to keep traffic moving when the lights went off. Film production came to a halt for two hours at the city's Cinecitta studios and at least one hospital was hit briefly.

Restaurant owners throughout the country worried that food in their refrigerators would go off.

Consumer groups complained that citizens had been given little notice.