Action News has obtained three tapes of what appears to have been a much larger collection. They may reveal what law enforcement agencies have long believed, that there are al-Qaida sleeper cells out there casing large metropolitan areas like Philadelphia. The tapes were found in a North Philadelphia rooming house after 9/11. The man who found them only recently looked at them. He was alarmed by what he saw and brought the tapes to Action News. We turned them over to the FBI. Linda Vizi/FBI: "It is obviously something we would have loved to take a look at early on."...