A tourist from Texas was run over and killed by a duck boat while crossing the street in Philadelphia.
The Ride the Ducks vehicle was itself carrying 28 tourists, as young as 10, when it hit Elizabeth Karnicki, 68.
Ms Karnicki had been in the city with her husband, who was a few feet ahead.
According to Sky News, some witnesses said the woman had been distracted by a tablet device or phone, although this has not been confirmed.
Chief Inspector Scott Small told philly.com: "The husband heard her scream, turned around, and saw that his wife had been struck."
She died at the scene on Friday at 5.20pm local time.
Small said it appeared to have been a "tragic accident" , and the 72-year-old driver is unlikely to be charged.
Ride the Ducks' vehicles tour the city's historical and Art Museum areas and points in between. The tour also includes a 20-minute cruise on the Delaware River.
Emily Myers, general manager of Ride the Ducks, told philly.com on Friday: "The thoughts and prayers of the entire Ride the Ducks organisation are with the family and friends of the pedestrian involved in an accident that occurred this afternoon."
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