A series of strong aftershocks rattled south-central Chile yesterday, panicking residents nearly a week after one of the most powerful earthquakes on record rocked the area and killed hundreds of people.

The government of outgoing President Michelle Bachelet, already facing criticism for its slow response to the quake, said it was revising faulty death toll figures after authorities mistakenly tallied scores of missing who later turned up alive.

Many people who survived Saturday's 8.8-magnitude quake were killed hours later by a massive tsunami, outraging Chileans who say there was no warning the waves were coming.

The Chilean navy has acknowledged there was a breakdown in its tsunami-alert system, and yesterday it fired the head of the agency in charge of issuing catastrophe warnings.

In the ravaged city of Concepcion, the country's second largest, some people ran out of their houses or jumped out of the vehicles they have been sleeping in since their homes were destroyed as seven intense tremors shook the area yesterday.

The strongest of the aftershocks was a magnitude 6.6.

"Some chunks of buildings that were already in bad condition fell, but nothing significant," the top government official in quake-hit Bio Bio region told local radio.

Last Saturday's quake, and a series of giant waves that followed, destroyed hundreds of thousands of homes, wrecked bridges and roads, and cracked modern buildings in half in the capital, Santiago. It also wreaked havoc on some of Chile's famous wineries and briefly shut down some of the world's richest copper mines.

The navy said there was no risk of tsunamis from the new aftershocks and people did not stray too far into the streets of Concepcion since the army had imposed a curfew until mid-day to control sporadic looting.

"It was terrible," said a frightened elderly man outside his house. "The three aftershocks that we just felt were very strong, I don't know when this is going to end."

The government said on Thursday the death toll, previously reported as 802, was unclear due to confusion over who was missing. Officials said they had identified 279 victims but were not sure how many bodies were unidentified.

Chile's two major newspapers yesterday said the government had revised down its calculation of fatalities in the hard-hit Maule region to 316 from a previous 587.

The confusion over the death toll prompted harsh criticism of Chile's National Emergency Office, known as Onemi, which President-elect Sebastian Pinera has pledged to overhaul.

In a blog posted on the daily El Mercurio website, the former head of Onemi, Alberto Maturana, called the agency's handling of the disaster "a comedy of errors".

"The agency has no validity in public opinion, when it is supposed to be the most credible," he was quoted as saying.