Smoking coil pack

[kazinhouse]

Hi first time posting. Ok went town today and car cut out after sounding very rough. Got towed home, fuse in engine compartment had blown. managed track this down to being a knackered coil pack. Have replaced coil pack ht leads and spark plugs. Car started was still very rough sounding. Next minute smoke comes out from the new coil pack, which has now melted. Now stuck as to what this could be. The original coilpack had also melted when we took it out. Any ideas would be helpfull as to what to check before puting another new coilpack on. Cheers in advance. forgot to mention its an 02 1.8 petrol