(CNN, NPR & AP ) Clinging to the hope of finding more survivors, rescue workers scoured mountains of rubble Tuesday where houses and schools once stood.
But as they searched through the night and Tuesday morning, the sobering death toll continued to climb in this city far too familiar with nature's wrath.
The vicious tornado that ripped across central Oklahoma on Monday killed at least 51 people -- with about 40 more bodies expected to arrive at the Oklahoma state medical examiner's office, Amy Elliott of the coroner's office said. Roughly half of the expected bodies are children.
The official death toll will gradually rise from 51 as each of the bodies are processed, Elliott said.
Already, at least 20 of those killed were children, including seven from Plaza Towers Elementary School in Moore -- the site of a frantic search Tuesday morning.
The school was in the direct path of the storm's fury. About 75 students and staff members hunkered down in Plaza Towers when the tornado hit, CNN affiliate KFOR reported.
At one point, an estimated 24 children were missing from the school, but some later turned up at nearby churches. It's unclear how many may still be trapped in the wreckage, and how many are dead or alive.
An early estimate rated the tornado as an EF4, meaning it had winds between 166 and 200 mph, according to the National Weather Service.
The death toll has far surpassed anything the city has seen from a tornado -- and is expected to climb.