When Associated Press photographer Sue Ogrocki saw the tornado warnings for the Oklahoma City area Monday, she didn't run into a storm shelter or take cover in her office.

She grabbed her camera equipment and her car keys. Then she rushed outside, got into her car and raced towards the approaching twister.

"We had advanced warning that tornadoes would probably be developing again yesterday afternoon," Ogrocki told ABC News. "So I know I had to get down here quickly. I had to get down here before it hit or at least be on my way before it hit."

A fire burns in the Tower Plaza Addition in Moore, Okla., following a tornado, May 20, 2013. Credit: Sue Ogrocki/AP Photo

Today, the National Weather Service said that Monday's tornado, which killed at least 24 people and injured hundreds when it sliced a 12-mile-long path of destruction from Newcastle to Moore, Okla., is the first top-of-the-scale EF-5 tornado of the year. The EF-5 rating, based on wind speed and inflicted damage, means winds exceeded 200 mph.

The monster twister, reportedly 1.3 miles wide, flattened homes, schools and hospitals, blowing out walls and windows. It uprooted trees and power lines. It tossed cars onto roofs of buildings like toys.

Ogrocki was one of the first news photographers on the scene in Moore. The images she captured have become some of the most iconic to come out of the disaster.

Moore police dig through the rubble of the Plaza Towers Elementary School following a tornado in Moore, Okla., May 20, 2013. Credit: Sue Ogrocki/AP Photo

When she arrived in Moore, Ogrocki said she saw devastation immediately. When she came upon a group of people standing next to a mammoth pile of rubble, she parked her car and got out. She said a woman told her it was a school.

"When I ran to the corner and saw the building, I didn't even know that it was a school. I had to ask someone," Ogrocki said. "But that's where, I think, the best images came from, and they were images of children being saved."

For the next 30 minutes, Ogrocki snapped photos of first responders working frantically to pull children, teachers and staff out of the mangled pile of bricks and metal that used to be Plaza Towers Elementary school.

Boy is pulled from beneath a collapsed wall at the Plaza Towers Elementary School following a tornado in Moore, Okla., May 20, 2013. Credit: Sue Ogrocki/AP Photo

A woman is pulled out from under tornado debris at the Plaza Towers School in Moore, Okla., May 20, 2013. Credit: Sue Ogrocki/AP Photo

"What I saw through my lens yesterday was kind of like a saving grace, because there was all this destruction here and bad things and people died, but what I got to see was people getting saved," she said. "And you don't get to see that very often as a news photographer."

Ogrocki watched young kids being pulled one after another out of the debris, which she said was "so heavy and so thick" that it seemed amazing anyone was being found alive. Bystanders, some of them parents, waited anxiously with her as she focused her lens on each of the children's faces when they emerged.

"Every time a child got pulled out of there it was just a sense of relief," Ogrocki said. "'Oh, another one, she's okay, he's okay. They looked scared, but they don't really look like they are hurt.'"

A child is pulled from the rubble of the Plaza Towers Elementary School in Moore, Okla., and passed along to rescuers, May 20, 2013. Credit: Sue Ogrocki/AP Photo

Boy is pulled from beneath a collapsed wall at the Plaza Towers Elementary School following a tornado in Moore, Okla., May 20, 2013. Credit: Sue Ogrocki/AP Photo

Of the at least 24 lives the storm claimed in Moore, the Oklahoma medical examiner said that seven of them were children. But Ogrocki said all of the kids she watched being pulled out of the flattened school were alive.

"To actually witness the saving, it's an incredible feeling," she said.

Credit: Sue Ogrocki/AP Photo