Ford Tranist, Capt Claret,
see these photos of the LPT area:
Flickr: sb_sfo's Photostream
You will see that all of the blades have come off the rotor and are now lying in the rear of the engine. Perhaps if it is the IPT disc that came out (or part of the disc) the enormous imbalance as the disc came out, could have cause the LPT to run very eccentrically, forcing the blades to distort and impact themselves and the LPT stator vanes.
In fact one photograph shows blades mising right through to the HPT NGV's, meaning LPT 1,2,3 and IPT blades are gone. Considering this is a large amount of metal and the fan at the front of the engine was windmilling merrily, as the a/c still had significant fwd speed, this would be why the sparks didn't stop for some time.
This is of course pure supposition and rumour...
Best Regards,
N1 Vibes