WASHINGTON—U.S. officials are growing concerned that giant Chinese-made cranes operating at American ports across the country, including at several used by the military, could give Beijing a possible spying tool hiding in plain sight. Some U.S. officials have compared ship-to-shore cranes made by the China-based manufacturer, ZPMC , to a Trojan horse. While comparably well-made and inexpensive, they contain sophisticated sensors that can register and track the provenance and destination of containers, prompting concerns that China could capture information about materiel being shipped in or out of the country to support U.S. military operations around the world.

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