Trading standards officers are concerned about hundreds of thousands of cheap chargers that are being sold in the UK.
Preliminary tests of the chargers, which are being shipped over from China and sold on the cheap, show that they are prone to overheating and, in some cases, can even electrocute owners.
One of the chargers concerned has the code marking DE62347066. Others have no code and are called Travel Charger, says the Beeb.
A specific warning has already been issued about chargers marketed as being for Nintendo DS and DS Lite machines, but which could also be used to charge Gameboy machines.
Trading standards officers are trying to recall the chargers.
Chris Holden, senior trading standards officer at Buckinghamshire County Council, told the BBC that it is a huge problem: "The UK appears to be flooded with them. It probably runs into hundreds of thousands or even millions".
He added that the chargers are being sold for about £5 on the Internet and about £6 in shops.
Safe chargers, which have been checked properly, retail for around £15.