At 04:30pm on July 19, 1952, the attention of Customs Inspector Sr. Domingo Troncoso, then with the Peruvian Customs Office at Puerto Maldonado on the jungle frontier with Bolivia, was called to a very strange cigar-shaped flying object over the river area. The big dirigible-shaped craft was flying horizontally and fairly low in the sky, passing from right to left from the observers position. It was leaving a dense trail of thick smoke, vapor, or substance on its wake. This object was a real, structured, physical machine and may be seen from its reflection in the waters of the Madre de Dios river underneath it. The object was estimated to be over a hundred feet long.

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