(FOX NEWS) A grim online warning from a self-described American jihadist said Sunday's terror attack in Texas was the work of ISIS and that the terrorist group has scores of "trained soldiers" positioned in 15 states, awaiting orders to carry out more operations.
The warning, which was posted on a file-sharing site, could not be verified, but was signed by Abu Ibrahim Al Ameriki.
That name matches the moniker of a shadowy American known to have joined a terrorist group in Pakistan several years ago and who has appeared in propaganda videos before. The chilling threat named five of the states where it is claimed that ISIS has terror cells in place.
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