They said the fuel might have damaged some sensors on the cars in question, causing them to lose power or quit altogether. The weird part is that most of the cars affected are 2-5 years old. The newest cars don't seem to be having any adverse reaction to the same gas. The fuel in question had been purchased mainly at supermarket stations like Tesco and Morrisons, but both of those companies said they can't find evidence of any contaminants in their supply. Greenergy, the company that supplies fuel to Morrisons and Tesco, says it will look into its own supplies, as well. Reminds us of the station here in the States that accidentally filled one of its storage tanks for gasoline with diesel fuel back in October, subsequently killing many vehicles over the period of a few days before the mixup was discovered.
Thanks for the tip, Vinny!