fact-checkedreputable news agencyproofread Avoid using free public phone charging stations, FBI Denver warns type='text/javascript'> googletag. display('div-gpt-ad-1453799284784-2'); }); >"Bad actors have figured out ways to use public USB ports to introduce malware and monitoring software onto devices," FBI officials announced in a tweet. The free public charging stations have multiplied in recent years as operators of airports, including Denver International Airport, increase services to accommodate growing numbers of people in transit