The rescue efforts were reportedly frantic, and the extent of the injuries is not currently known.
The Amphibious Duck, a tourist boat, overturned when it collided with a barge. Two Coast Guard vessels arrived to rescue people from the water, while fire and police lent assistance.
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Another eyewitness, Terri Ronna, of Oakland, NJ, told CBS News that she was crossing the river by ferry from Camden, NJ, to Philadelphia when the captain announced that someone on another ship had fallen overboard and that they were going to rescue him.
"We were not even halfway over when they said there was somebody overboard and we were going to get them," Ronna told CBS News. "There were people all over; we could see all these orange life vests."