Most of those injured in Saturday's quake were in Boumerdes, a city 50 kilometers (30 miles) east of the capital.

It was another aftershock of the earthquake last May 21 that killed 2,300 people and injured more than 11,000, the Algerian Center for Astronomy, Astrophysics and Geophysics (CRAAG) said.

Saturday's recent quake, recorded at 7:40 pm (1840 GMT), was the largest of more than 1,000 aftershocks registered so far, measuring 5.7 on the Richter scale, according to radio reports.

"I was so scared. I thought we had finally finished with these aftershocks, which have set everyone on their nerves since last May and June," said Kamel, a university student visibly tired after a sleepless night spent mostly on the street.

Mustapha, a resident of an eastern suburb of Algiers, said he would not stay outdoors despite his fear. "These aftershocks have deeply upset me, but I have no choice -- I have to go home, since it's freezing outside."

By midday Sunday, most of the injured, who were reported more panicked than hurt, had left the hospital, health official Mourad Redjimi told the radio. "There are fewer than 10 people left (in hospitals) who are in need of serious treatment."

No structural damage was reported from Saturday's quake, but electricity was cut in the Boumerdes region, the civil protection services said.

The epicenter was the same as that of the earthquake last May -- at Zemmouri, a small town near Boumerdes that was flattened in the 2003 quake, which measured 6.8 on the Richter scale.

The director of CRAAG, Mohamed Hamadache, said earthquakes were a fact of life in this stricken region.

Residents of Algiers and its outlying areas will have to learn to "live with this phenomenon, which affects all of northern Algeria," Hamadache said. "We will always have earthquakes. So we should learn to live with them by undertaking initiatives necessary to reduce the impact of a large aftershock or quake."

Boumerdes was the hardest hit by the May quake, which left up to 100,000 people homeless.

The disaster unleashed an avalanche of anger in Algeria against the government for its slow response, and against corrupt property developers, whose shoddily built housing collapsed during the earthquake.

Hundreds are believed to have died as emergency services turned up late or not at all in the region, trapped in buildings which had clearly not been quake-proof, in violation of regulations on the books since 1980, when Algeria's worst quake struck killing some 3,000.

TERRA.WIRE