The other day the batteries in my camera started to get really hot spontaneously, so that I had to take them out and chuck them away - the camera wasn't even switched on. I've never had this happen before - can anyone explain it? (They were really cheap AAA ones - the kind that come already fitted in a toy and that last about 10 minutes).
This sounds like the batteries short circuited.
Shame you threw them away but I'd guess as they were cheap, the plastic wrapping wasn't complete and the long body part somehow shorted to the top cap.