The Iranians sent a couple Frogfoots after it. The Sukhoi Su-25. It's like the dimwitted little brother of the A-10 that ate paint chips growing up, so I'm not really surprised.
ETA: Also, educated guess on the drone, since the story says it was flying along the Iranian national waters boundary at a distance of 16 miles from the coast, I'm betting it wasn't a Predator. Typically when we want to sneak a peek into another country *coughpakistan* without actually entering it, we have two choices: Re-tasking a spy satellite (really expensive), or sending up a Globalhawk to run up and down the border while peering into their country from 60,000+ feet.
If it was a Globalhawk or a Reaper the Su-25 wouldn't have a snowballs chance in hell of taking it down.