Type unconfirmed, but from the vid it seems to be a Kiran, given the importance of the show I would not be surprised to see a major navy team involved, probably "Sagar Pawan". A friend of mine who has seen another vid I cannot locate claims on the net there was contact of #4 (trailing) with #3.
The BBC provided vid is inconlcusive as nothing strange can be viewed, I guess more amateur vids will be coming up soon.
The comments of the Indian TImes reporter are the normal stuff, do not really make sense (AFAIK one initiated ejection sequence from whatever position triggers the other in modern a/c? "Entangled"? This must be exterior I guess...?) , even if he was an eye witness:
http://news.bbc.co.uk/2/hi/south_asia/8546735.stmA Times of India journalist, Kingshuk Nag, witnessed the crash.
He told the BBC that the plane "went down in a manoeuvre, but could not come up".
"One pilot tried to eject but got entangled with wires and died. The other died in the crash," he said.