Rescuers searched for survivors along Japan's western coastline after a powerful earthquake as aftershocks and tsunami warnings added to the challenges. The death toll rose to 77 with 35 people still missing as weather forecasters warned of heavy rain and landslides. Disaster experts emphasized the need for an accurate damage assessment and proper response. The first 72 hours are especially critical for rescues, experts said, because the prospects for survival greatly diminish after that.