While without better pics or seeing the coin in person, I can't be certain to the error, I copied and pasted the pic to my' computer, blew the pic up and believe that the coin was "Struck Through" by a piece of de-lamination that separated from another coin. I state this because even though there are linear (orientated along the length of the error) striations in the struck through area that are consistent with the appearance of a lamination separation (de-lamination) error, the coin's surfaces inside the struck through area appear to be too smooth and hard to be a Lamination separation and the toning in the struck through area is the same as the rest of the coin (i.e. the area inside the struck through area is not rough with pieces of metal sticking out and/or up and/or overlapping and the toning is not different from the toning on the rest of the coin). This points to the offending piece (de-lamination piece from another coin) separating from the O.P.'s coin not long after the coin was minted/struck.
Frank