One of the videos does appear to show burning materials landing on the bridge deck, possibly unexploded material from an improvised device?
I'm guessing the 1 or 2 spans which fell undamaged can be craned back up into place relatively quickly (assuming they are undamaged). The broken span will need to be replaced, which will take quite some time.
That said I wouldn't like to be a member of the crew tasked with repairing the bridge. The Ukes may take a leaf out of Russia's playbook and attempt a 'double-tap'