The 10-year-old had been out injured since being narrowly pipped to the 2011 RSA Chase at the Cheltenham Festival.
"Unfortunately he broke a hind leg up high behind this morning and I just feel so sad for everyone in the yard and especially [owner] David Johnson, who was good enough to send the horse to us in the first place," Elliott said.
"He was a Grade One winner and just got touched off in the RSA.
"It's devastating for everyone connected with the horse."
Elliott also confirmed that the horse was looking at making a run for the Grand National at Aintree in April.