PHILADELPHIA (AP) -- Searchers are plying the murky waters of the Delaware River for two passengers missing from an amphibious Philadelphia sightseeing boat that was struck by a barge, flipped over and sank.

Police say the 37 people aboard the six-wheeled duck boat were tossed overboard Wednesday when the barge hit it after it had been adrift for 10 minutes with its engine stalled. Most of the people were plucked from the river by other vessels just south of the Ben Franklin Bridge.

The Coast Guard said it would search through the night and into Thursday for a 16-year-old girl and a 20-year-old man believed to have been aboard the duck boat, which can travel seamlessly on land and water. Coast Guard Capt. Todd Gatlin says hope is fading but th

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