We had just switched it on with some chipped potatoes in and luckily my dh was still in the kitchen so managed to switch it off at the plug. Had we left it unattended it could have been quite seious as there were flames coming out of it.
Not very impressed, to say the least, we have this Actifry for just a year and it was a replacement for the first one we had that also devolped a problem { not of the flaming variety though } within the first year.
Please be careful if you also have an Actifry !