TEHRAN — Iranians turned their efforts from rescue to relief Sunday after twin earthquakes that killed more than 300 people, trying to provide medical care for more than 2,000 injured and shelter and aid for thousands left homeless.

For a second night in a row, survivors of Saturday's magnitude 6.4 and 6.3 quakes in a northwestern province were advised to sleep outside for fear of continuing tremors. Bulldozers were already at work starting to clear up the rubble left from several destroyed villages.