ROME -- Italians were told that a blackout like the one that darkened North America last month couldn't happen to them. A day after power went out on the entire peninsula, anger mounted Monday over the country's dependence on imported energy and resistance to building new power plants.

Local politicians, consumer advocates and others called on the national government to take action against whoever is responsible for the outage that cut power to some 55 million people -- 5 million more than were affected by the Aug. 14 U.S. blackout.

'We'll ask for the heads'

Nearly everyone in Italy lost power, and electricity wasn't restored fully until 9 p.m. Sunday, 18 hours after the blackout began. Four deaths were blamed on the blackout, including a 92-year-old woman in Puglia whose clothes caught fire from a candle flame.

"We'll ask for the heads of all those responsible," Salvatore Cuffaro, the head of Sicily's regional government said.

Sicily was the last to have all its power, which particularly irked Cuffaro because the island supplies the country with half its energy.

A consumer advocacy group, Adisconsum, joined the critics, demanding prosecutors help ascertain responsibility, "so we know to whom we should present the bill."

Industry Minister Antonio Marzano ordered an inquiry, but said an investigation had yet to determine the precise trigger of the outage.

The Swiss power company Atel said that an old fir tree had toppled onto a power line, setting off the problem. But an Atel spokesman, Rolf Schmid, insisted that a connection error by an Italian grid operator caused the cascading power loss throughout Italy.

Etrans, the coordinator of the Swiss high tension network, said in a statement that just a few minutes after the tree fell, the person who coordinates with the Italian network called his Italian counterparts to tell them to increase production.

"According to the information we have, the Italian reaction was much too slow, to such an extent that from 3:30 a.m. the lines from France, Switzerland, Austria and Slovenia were overloaded and disconnected one after another," Etrans said.

Nearly immediately after power failed, Italian authorities blamed the cut on France, which provides Italy with a major source of electricity and a backup line.

But France faulted Italy.

The head of France's grid operator RTE, in an interview in Monday's Liberation, a French daily, called Italy's dependence on imported energy "unusual."

"We must build other interconnection lines between Italy and the rest of Europe," said RTE's Andre Merlin.

The head of Italy's GRTN electrical network, Carlo Andrea Bollino, warned people to avoid elevators Monday because of a series of planned, localized blackouts throughout the day while lines are tested.

The advice was galling to those recalling Bollino's assurances soon after the North American blackout that Italy wouldn't go dark.

Secure, vulnerable

Back then, Bollino boasted that Italy's network was more modern and reliable than the system shared by parts of Canada and the United States.

Bollino, in an interview Monday in Turin's daily La Stampa, acknowledged he was wrong.

"Our system is more secure than the American one, but it's also more vulnerable," because of its reliance on imported energy, Bollino said.

Italy imports nearly 17 percent of its power; the European average is 2 percent.

Because of anti-monopoly regulations, Italy's largest electricity supplier, Enel, can no longer build more plants. Newer, smaller power companies will have to pick up the slack, but local opposition has discouraged construction.

A bill calling for the construction of several more power plants has languished in Parliament for more than a year.

Power officials said it is often cheaper for Italy to import energy than to produce it.

Italian President Carlo Azeglio Ciampi, in Paris Monday to lunch with French President Jacques Chirac, said the two countries need "even closer ties in the energy field."

Ciampi, during a ceremony in a dark hall in Naples on Sunday, took Italians to task for opposing the construction of power plants in their neighborhoods.

Marzano, who was due to brief lawmakers Tuesday about the blackout, said he would tie the plant construction bill to a confidence vote, putting the government's survival on the line to speed passage of the legislation.

For a nation that voted in a 1987 referendum against nuclear power, the blackout could prove to be a galvanizing jolt.

"It's only a matter of time before it happens again," said Luca Biagiotti, a theater director in Leghorn, northern Italy, who was stranded in Rome when trains stopped running.

No total bill for losses has been released, but an industrial lobby said the cost to restaurants and bars in spoiled products and lost sales totaled $139 million.