Sister Margaret Ann became an online sensation when she was spotted at work by an off-duty police officer. Sister Margaret Ann's good deed became an online sensation when she was spotted by an off-duty police officer. (Photo: Miami-Dade Police Department/Facebook)

Nuns may be the stuff of Catholic school kids' nightmares, but this nun is also a hurricane action hero.

Sister Margaret Ann didn't want to sit idly by while people were sidelined and suffering after Hurricane Irma. So the principal of Archbishop Coleman F. Carroll High School, southwest of downtown Miami, went into her school's supply closet and grabbed a chainsaw.

"They didn't belong there. They needed to be used," she matter-of-factly explained to CNN.

A Miami-Dade off-duty police officer happened upon the nun, who was trimming a downed tree with a roaring chainsaw. He took a photo and shared some video of her at work on the department's social media. Not surprisingly, it struck a chord.

"The road was blocked, we couldn't get through," Sister Margaret Ann told CNN. "And I saw somebody spin in the mud and almost go into a wall, going off the road. So, there was a need, I had the means — so I wanted to help out."

By pitching in, the nun said she was just practicing what they preach at school.

"We teach our students, 'Do what you can to help other people, don't think of yourselves,'" she said. "That's what I wanted to do."

Her words and actions certainly resonated with the hundreds of people who commented on the Twitter and Facebook posts that featured her.

"Somebody made a comment that she was not handling the chainsaw correctly," wrote Eggert Edwald. "I was raised 'do the best you can and after the day you can go home proud.' That is all we ask for, she rocks."

"As a friend wrote when I shared this 'This is all sorts of awesome!'" wrote Janice Boyd. "Couldn't have said it better!!!! God bless you Sister!!!!"

And, of course...

Watch as Sister Margaret Ann talks to CNN about her hurricane cleanup work:

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