A strong earthquake that hit Mexico City and other central areas has killed at least 245 people, officials say. Search teams are working feverishly to find any survivors who were trapped — including at least one girl who's among students caught when the quake turned their school to rubble.The girl, 12, has been able to communicate with emergency crews, and she has wriggled her fingers for them through the wreckage. She was located alive in the debris of the Enrique Rebsamen School, south of the capital. The building collapsed during Tuesday's 7.1-magnitude quake.After visiting the site, NPR's Carrie Khan reports: "It is a heartbreaking scene. Hundreds of volunteers and rescue personnel have flooded to this neighborhood around the school ... all are emotionally drained, tired, but just holding on to hope they can reach some of the children alive ... under all that rubble. "One wing of the school, three stories just pancaked in the powerful quake. One right on top of the other, making the rescue effort and chances of survival very difficult. "But the volunteers keep coming ...with hard hats and fluorescent vests. They're removing the rubble with picks, shovels, their hands...whatever they can. And dozens more are taking in donations, feeding the rescuers, just wanting to be there and do something for those children either dead or trapped in the building."Rescue workers have spent hours trying to free the girl and anyone else who might have survived. In addition to heavy rubble that sits precariously in the debris pile, the effort has been frustrated by heavy rain that fell overnight.The girl's name is Frida Sofia, a doctor who's working with the rescue team tells the Associated Press. The doctor added that the girl says there are several other children near her who are also alive.The name Frida Sofia became a top-trending term on Twitter — but there are questions over whether it's the girl's name. Media outlets in Mexico have reported it, especially after journalist Joaquín López-Dóriga tweeted it. But teachers say there's no student at the school with that name — and El Universal reports that a rescuer used the name as a way to communicate with the girl.All the same, El Universal's main headline on Thursday reads, "The hope of Rebsamen is called 'Frida.'"Authorities say they've pulled dozens of survivors from damaged buildings. But Mexico City's Mayor Miguel Ángel Mancera says more than 35 buildings collapsed, from offices and apartments to schools.Mexico City's metro service says it's allowing people with rescue tools — picks, shovels and mallets — to ride on its vehicles. And for the second day, the service is free."President Enrique Pena Nieto has declared three days of mourning for victims of the quake," Carrie reports. "Schools in the capital and surrounding affected states remain closed until Monday."In Mexico City and outlying areas — including the city of Jojutla, in Morelos state, where many houses and buildings were reduced to rubble — soldiers, police, firefighters and volunteers have alternated between working to find survivors and undergoing pauses of total silence, as rescuers call out for anyone who's still alive to respond."While many eyes are on the earthquake effects in Mexico City, this town of 20,000 people was crumbling," James Fredrick reports from Jojutla for NPR. "Its old abode buildings were no match for the 7.1 quake."Jojutla Mayor Alfonso de Jesus Sotelo "says 2,000 buildings are damaged, 300 of those totally collapsed; 16 people have died, including four children," Fredrick says."Definitely this loss is unsustainable," Sotelo says. "We are out of control, being able to correct or absorb the cost that's involved."If initial reports and relief efforts seemed to focus on Mexico City, Fredrick reports, "A day later that has changed: Hundreds of young volunteer rescue workers line up to clean rubble. Donated bottles of water and canned food pile up all over the town."In Puebla, where the epicenter of the quake was located in the western part of the state, Gov. Antonio Gali gave a grim account of the losses on Thursday morning."We have 43 dead and 117 injured," Gali told FORO TV. He added, "We have 9,772 affected homes and 1,632 total losses." Copyright 2017 NPR. To see more, visit http://www.npr.org/.