More than 50 survivors have been plucked from disaster sites in Mexico City since Tuesday afternoon’s 7.1-magnitude quake, and first responders, volunteers and spectators joined in chants of “Yes we can!”

The death toll was at least 233, revised down from 237 earlier on Thursday, according to Mexico's head of civil protection Luis Felipe Puente. In Mexico City 1,900 were injured. (For graphic, click tmsnrt.rs/2xxlUTz)

As the chance of survival diminished with each passing hour, officials vowed to press on, heartened by a few success stories.

Late on Wednesday night, an eight-year-old girl was rescued from a collapsed building in the Tlalpan neighborhood, nearly 36 hours after the quake, local officials said.

After more than a day of wall-to-wall television coverage of the search for a girl in the rubble of the Enrique Rebsamen School in the south of the capital, the Mexican Navy changed its version of events and said all pupils were now accounted for.

“We have done a count with the school authorities and we are sure that all the children, either tragically, died, or are in hospital, or safe at home,” said senior Navy official Angel Enrique Sarmiento.

Mexican television stations, led by broadcaster Televisa, had cited rescuers as saying that a schoolgirl was trapped in the rubble. An admiral in charge of the rescue effort at the school had confirmed that.

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