ASUNCION, Paraguay -- A stray dog is getting credit for thwarting a prison break.

Officials say three dangerous inmates dug a tunnel about 26 feet from their cell to the street and were about to break free just before dawn when the dog began to bark and alerted a guard.

Authorities at the Tacumbu prison on the southern edge of the capital dragged the unlucky prisoners before the media on Friday to tell the tale.

"Because of a stray dog we couldn't escape," complained Hilario Villalba. "When I reached the street, sticking my head out, the stupid dog barked and alerted a guard."

Villalba, who is serving a 30-year double-murder sentence, vowed in his native Guarani language that he'll keep keep trying to escape because he said his sentence isn't fair.

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