For a little while Wednesday afternoon, customers at an ATM in Texas got a curious extra with their cash. Along with a receipt detailing their transaction, they got a little slip of scribbled-on white paper.

It was a plea for help from the man trapped inside.

"We have a once-in-a-lifetime situation that you'll probably never see or hear about again," Corpus Christi Police Officer Richard Olden told a local Fox affiliate.

As Olden tells it, a contractor had been installing a new lock on the service room of a Bank of America ATM. Trouble is, the man — whose name has not been released — left his phone in his truck. So when the door closed behind him and refused to open, he had no one to call and no way to make his voice heard intelligibly through the machine.

"You can't just turn the knob and exit," Corpus Christi police spokesman Lt. Chris Hooper pointed out to The Washington Post.

The trapped man did have paper and a pen, however.

"So people are coming by and using the ATM machine because it's still operational, and he's slipping notes through the ATM, through where you would get your receipt," Olden said.

"Please help," one note read. "I'm stuck in here and I don't have my phone. Please call my boss."

Customer after customer assumed — quite understandably — that the notes had to be a prank.

Eventually, a good Samaritan took the situation seriously and contacted the cops. Though at first, Olden admitted, even the officers first on the scene thought it was a prank, too.

"We come out here, and sure enough, we can hear a little voice coming from the machine. So we're all thinking this is a joke — this has got to be a joke," Olden said.

But after passing some shouts back and forth, the officers went around and busted down the problematic door. And because no crime was committed, the man was not only free, but he also was free to go.

"But you'll never see this again in your life," Olden said. "It was just crazy."

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