EGION, Greece (AP) _ Tracking a faint knock, workers crawled through a collapsed apartment building's debris Saturday, searching for survivors of an earthquake that killed 24 people and injured more than 60.

But they found only more danger as aftershocks rocked the region.

Rescuers said they heard someone knocking as Swiss and French teams used sonar listening devices deep in the cracks of the rubble. French civil defense member Alain Ricci said there was ``a sign of life, not very strong, but there is one. Someone was knocking.''

``Now our job is to work as fast as hell,'' said Capt. Didier Guinard, head of the French group working in this southwestern port town.

After hours of digging, rescuers seemed no closer to finding the source of the knocking _ or, for that matter, finding anyone else alive 60 hours after the magnitude 6.1 quake.

The death toll reached 24 when the bodies of a man and young woman were found Saturday, crushed under a cement slab. Nearby, workers found seven live canaries in their three cages.

As the workers dug in an area where they believed more bodies lay, aftershocks to Thursday's quake rolled through Egion and set off fears that a wall of the five-story apartment building would collapse on them.

An 8-year-old boy buried beneath the apartment house debris was rescued Friday night.

Greeks watched on television as rescuers carried out Andreas Bogdanos and placed him on a stretcher as his father stood by. As he was carried to an ambulance, he tried to raise his arm and wave to an applauding crowd.

Andreas was trapped in the debris of the apartment house when the quake struck at 3:15 a.m. Thursday. Doctors said the boy was in good condition.

The quake demolished or damaged more than 2,000 buildings in Egion and its environs in the Gulf of Corinth area, 90 miles southwest of Athens.

Two columns of an ancient temple at Delphi were slightly damaged.

Premier Andreas Papandreou arrived in Egion by helicopter for a brief visit and offered local officials aid to rebuild homes.