(MOORE, Okla.) -- At least seven children killed in the devastating tornado that tore through Moore, Okla., were from Plaza Towers Elementary School, officials said.
The school was destroyed by Monday's tornado, which tore a 12-mile path of destruction that left at least 24 people dead.
The deadly twister touched down just as students were about to be released for their last week of school before summer vacation. Many of the students hunkered down in closets, classrooms and bathrooms, clinging to their classmates and teachers.
Oklahoma County Commissioner Brian Maughan confirmed to ABC News affiliate KOCO-TV on Tuesday that a number of children at Plaza Towers Elementary School remain unaccounted for.
"It's just a very graphic situation for even those of us who've come obviously well after the storm has passed," he said.
The walls of Plaza Towers Elementary School were "pancaked," Oklahoma Lt. Gov. Todd Lamb told ABC News.
Moore officials and National Guard members told ABC News the search-and-rescue operation at the school is now a body-recovery effort.
"I know there's a number of dead children from that school," Oklahoma City Police spokesman Sgt. Gary Knight said. "I know the number is around seven."
Briarwood Elementary School, also in Moore, received a "direct hit" from the twister and was also destroyed, with its roof and walls blown off.
One sixth-grade boy from Briarwood named Brady said he and other students took cover in a bathroom.
"I was in my classroom building and we were told to get in our tornado precaution system. Then they moved us to the boys and girls bathroom," he said. "Cinderblocks and everything collapsed on them but they were underneath so that kind of saved them a little bit, but I mean they were trapped in there."
Josiah Parker, 8, escaped Briarwood unharmed but couldn't find his parents in the immediate aftermath of the tornado.
"If our school is crushed, my house is like directly behind the pond and so I think it might be crushed, too. If my mom and dad are still alive, they're probably going to take us to a hotel," Josiah said.
Josiah's parents survived and the family was able to reunite.
Students remained at Briarwood despite the tornado warnings because there were safe areas where they could be protected.
Moore resident Andrew Wheeler credits a Briarwood teacher with keeping his son safe as the tornado wrecked havoc on the building.
"The teacher held their heads, and bricks and everything were falling all over the kids," he said. "She got her arm injured. One of the other boys on her other side got a big gash in his head, but he's OK."
Wheeler's son, Gabriel, says his teacher stood with the class the entire time and told them to act as they did in practice drills.
"The roof came off and then I felt something and it was just raining clay on me and all that," Gabriel said.
Monday's twister was the latest in a group of violent storms that swept through the Midwest, starting on Sunday, leaving dozens of people dead.
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