I thought that Hannibal fought with elephants in every Italian battle except Cannae? By then they had all certainly died.

Though I still think it's possible, I'm cynical about it. Were they African or Indian elephants? For the last one they'd have to go all the way to...well, India since the elephant population in the middle east had died out already in Roman times...
It would be logistically inpractical, and the shock value of a handful of them in this time probably wasn't very high.

EDIT: to clarify, by African I mean the African forest elephants, not the savannah dwellers.