The U.S. Coast Guard searched the murky waters of the Delaware River on Thursday for two passengers missing from an amphibious Philadelphia sightseeing boat that was struck by a barge, flipped over and sank, according to AP. The 37 people aboard the six-wheeled duck boat were tossed overboard when the tugboat-pushed barge hit it after it had been adrift for a few minutes with its engine stalled, police said. Most were plucked from the river by other vessels in a frantic rescue operation that happened in full view of Penn's Landing, just south of the Ben Franklin Bridge. The duck boat, which can travel seamlessly on land and water, had driven into the river Wednesday afternoon and experienced a mechanical problem and a small fire, officials said. It was struck about 10 minutes later by a barge used to transport sludge and sank to the bottom of the river. The Coast Guard said it would search through the night for a 16-year-old girl and a 20-year-old man believed to have been aboard the duck boat. «Hope is fading, but we're not giving up hope completely,» Coast Guard Capt. Todd Gatlin said Wednesday night. Ten people were taken to a hospital; two declined treatment, and the other eight were treated and released, Hahnemann University Hospital spokeswoman Coleen Cannon said. The National Transportation Safety Board said it planned to try to obtain any radio recordings, any possible mayday calls, photographs from witnesses or people aboard and other evidence as its investigators remain in Philadelphia over the next several days. NTSB member Robert Sumwalt said investigators would try to figure out why the vessels collided and «how conspicuous would that duck have been» to the tugboat pushing the 250-foot-long (75-meter-long) barge. NTSB officials also hoped to conduct witness interviews, he said. Police Commissioner Charles Ramsey said divers found the duck boat in water about 50 feet (15 meters) deep. Crews would not attempt to recover it until Thursday at the earliest, police spokesman Lt. Frank Vanore said. Some duck boats are amphibious military personnel carriers dating to World War II that have been restored and reconditioned. Known by their original military acronym as DUKWs, they were first introduced in the tourism market in 1946 in the Wisconsin Dells, where about 120 of the vessels now operate. As of 2000, there were more than 250 refurbished amphibious vehicles in service nationwide, the NTSB said.
