Broken Timing Chain

Went on a track day today, during the first session, while breaking and changing down I lost all power and the engine cut out and then wouldn't start.

In the pits I removed the cam cover to see a broken cam chain and damaged buckets. Once home I removed the head to see the extent of the damage. 

I found that I had 10 bent valves and the pistons look ok. Will remove the engine at the weekend to see if there is any more damage.