When Carmen Luiza Diaz de Cumare heard shouts about a body being pulled from a mountain of crumbled concrete, she scrambled up and around the bent and twisted rebar and over the crevices where an apartment tower once stood in this central part of the coastal Venezuelan state of La Guaira.

“We need help,” one survivor said, as Venezuelans search for loved ones and wait for aid after deadly earthquakes.

At a makeshift morgue in the quake-hit Venezuelan port of La Guaira, forensic experts in blue gowns and caps picked their way through dozens of bodies laid out in bags under the…