The letter bombs were sent in connection with the detention of the blind sheik Abdel Rahman and those responsible for the earlier World Trade Center bombing in 1993.

"Results": [
    {
        "TypeName": "PER",
        "Text": "sheik Abdel Rahman",
        "Start": 73,
        "End": 91
    },
    {
        "TypeName": "LOC",
        "Text": "World Trade Center",
        "Start": 130,
        "End": 148
    }
]