Transcript for Philadelphia Police Uncover Dungeon
The FBI and authorities in Philadelphia are piecing together clues on something so brutal they say they have not seen anything like this before. Here's ABC's Justice Department correspondent Pierre Thomas. The FBI has now joined an investigation of potential crimes that Philadelphia police are calling pure evil. Mentally disabled victims locked away held prisoner. While thieves stole their money in an identity theft scam that may stretch across the country it's unconscionable. -- all the way to describe it. The nightmare was revealed when the -- respondent to complaints about people sneaking into the basement of the Philadelphia apartment. The landlord found the -- door. Pushing it partially open and -- his flashlight into the darkness He discovered four people including -- man changed to a -- Police say the suspects had been stealing the Social Security disability checks of their prisoners. At least one of the victims of may have been held for years. To know that something -- that is more Norman within five feet away from me. -- -- -- The alleged -- -- Linda and Weston was convicted of locking a man and a closet and starving him to death in 1981. And there are fears tonight there could be more victims. Police have discovered documents with the names of fifty people from three more states Philadelphia police have begun calling police and other jurisdictions for help. The good news tonight the victims -- are recuperating well including -- Knowles who even found the strength to somehow after his ordeal. But it's a race against time police -- hustling tonight. They need to know if there are more victims they want to make sure no one else is locked away somewhere in the dark.
This transcript has been automatically generated and may not be 100% accurate.