MEXICO CITY, Sept. 20 (Xinhua) -- Rescue efforts at a toppled elementary school in Mexico City gripped the nation on Wednesday, one day after a massive earthquake reduced nearly 40 buildings to piles of debris in the capital.
The drama unfolded at the Enrique Rebsamen School in the south of the city, where a young girl trapped under the rubble managed to make contact with rescuers, but remained frustratingly beyond their reach.
Some 26 hours after the 7.1-magnitude quake hit Mexico a little past 1 p.m.(1800GMT) on Tuesday, hundreds of rescue workers, including soldiers, marines, firefighters and police officers, worked in shifts to free the girl named Frida Sofia.
At least one more minor and an adult were believed to be trapped at the school, but it was Sofia who had sent an SOS to her family from her cellphone and spoken to rescuers.
"What we have fully confirmed is that there is a young girl who is alive, is being communicated with, is being supplied with water, and that apparently, the rescue operation is increasingly closer," Public Education Minister Aurelio Nuno Mayer told local media.
Some 21 children and four adults at the school were confirmed dead, Nuno posted to Twitter; another 11 were rescued.
Worrying that the debris would cave in on the trapped, rescuers were sifting carefully through the broken bricks, twisted metal and fallen plaster, relying on high-tech thermal scanners and specially trained rescue dogs instead of using heavy machinery.
"We are using devices provided by the navy to scan for bodies," firefighter Jose Vazquez, a volunteer from Texcoco, central State of Mexico, told Xinhua.
Every 15 minutes or so, rescuers called for complete silence to be able to hear the girl and try to locate where she was, a marine explained to Xinhua.
Instructions had been scrawled in large yellow letters on the school fence -- "LEAVE" and "SILENCE" -- warning curious onlookers who could get in the way of rescuers.
"We are working nonstop because the more time passes, the more difficult the rescue is," a member of the city's rescue brigade told Xinhua.
As hours had elapsed, rescuers were considering supplying those still trapped under with food.
"We need hoses ... to feed the kids," one rescuer yelled.
Someone with a megaphone periodically shouted out a list of needs, including tools for digging, or broadcast some anxiously awaited good news.
Earlier in the day, the megaphone announced the names of two children rescued from the rubble, alive.
"Sergio Hernandez is alive! Little Sergio Hernandez is alive!"... "Myriam Gutierrez is alive!"
Anxious parents, teachers, neighbors and others broke into applause.
Sofia's name has yet to be called.
The earthquake shook the center of the country and killed at least 230 people, including 100 deaths in the capital Mexico City, the civil protection bureau said on Wednesday.
