Life has moved outdoor for many in the quake-shocked city of Juchitan, where a third of the homes are reported uninhabitable and repeated aftershocks have scared people away from many structures still standing.
The city is littered with rubble from Thursday night's magnitude 8.1 earthquake, which killed at least 90 people across southern Mexico - at least three dozen of them in Juchitan itself.
Officials in Oaxaca and Chiapas states said thousands of houses and hundreds of schools had been damaged or destroyed. Hundreds of thousands of people were reported to be without water service.
Many people continued to sleep outside, fearful of more collapses, as strong aftershocks continued to rattle the town, including a magnitude 5.2 jolt early on Sunday.
Local officials said they had counted nearly 800 aftershocks of all sizes since the big quake, and the US Geological Survey counted nearly 60 with a magnitude of 4.5 or greater.
Oaxaca Governor Alejandro Murat said that the death toll in his state had risen to 71, while officials have reported 19 killed in Chiapas and Tabasco states.
Juchitan's downtown streets grew increasingly congested on Sunday as dump trucks and heavy equipment hauled away debris and pushed smaller piles of debris into larger mountains of rubble.
Teams of soldiers and federal police with shovels and sledgehammers fanned out across neighbourhoods to help demolish damaged buildings. Volunteers, many teens from religious or community groups in surrounding towns that were not as severely hit, turned out in force to distribute water and clothing or lend a hand.