Rescuers race against time to find quake survivors in Mexico

Members of a rescue team hold a fellow rescuer by his feet during the search for students at the Enrique Rebsamen school in Mexico.

Rescuers laboured against the odds on Thursday to find survivors trapped beneath crumpled buildings in central Mexico following the country's deadliest earthquake in 32 years, as the search for a 12-year-old schoolgirl that transfixed the nation faced complications.
More than 50 survivors have been plucked from disaster sites in Mexico City since Tuesday afternoon's 7.1-magnitude quake, leading to impassioned choruses of "Yes we can!" from first responders, volunteers and spectators gathered around the ruins.
At least 237 other people have died and 1,900 were injured.
As the chance of survival diminished with each passing hour, officials vowed to continue with search-and-rescue efforts such as the one at a collapsed school in the south of the capital. At the site, Navy-led rescuers have communicated with the 12-year-old girl, but were still unable to dig her free.
Just as it seemed rescuers were going to save the girl, they had to suspend their work early on Thursday morning due to a collapse within the building's debris, local media reported.
Eleven other children were rescued from the same Enrique Rebsamen School, where students are aged roughly six to 15. Twenty-one children and four adults there were killed.
Rescuers had earlier seen a hand protruding from the debris and the girl wiggled her fingers when asked if she was still alive, according to broadcaster Televisa, whose cameras had special access to the scene to provide non-stop live coverage.
But some 15 hours into the effort, Admiral Jose Luis Vergara said rescuers could not pinpoint the location of the girl.
"There's a girl alive in there, we're pretty sure of that, but we still don't know how to get to her," he told Televisa.
"The hours that have passed complicate the chances of finding alive or in good health the person who might be trapped," he said.
Two days after the earthquake, danger in the capital persisted, with armed soldiers guarding abandoned buildings feared to be at the point of collapse.
"This area is evacuated because the building is at risk of falling. We are waiting for engineers who are going to evaluate... to see if we must knock it down," a soldier said in front of an abandoned building in Mexico's central Roma neighbourhood, one of the areas hardest hit by the quake.
As Vergara spoke, a human chain of hard-hatted rescuers removed a large chunk of concrete from the floodlit scene.
Rescuers periodically demanded silence from bystanders to allow them to hear any calls for help.
As with other disaster sites throughout central Mexico, officials have not employed heavy-lifting equipment for fear of crushing survivors. Some 52 buildings collapsed in Mexico City alone and more in the surrounding states.