Apple in China has posted instructions on how to tell an official power adapter from a fake one, after a number of iPhone owners claim to have been electrocuted by their handsets.

The page shows images of chargers for each Apple device, including the iPhone 5 and the iPad 2, with the safety notices underneath.

The recent electrocutions took place in the Chinese cities of Beijing and Xinjian, putting one man into a coma and killing another woman.

The site reads: ‘This overview will help you identify genuine Apple USB power adapter.

All iPhone and iPads are sold with official Apple chargers, although fake replacements can be bought online.

Earlier this week a Chinese man reportedly fell into a coma after suffering an electric shock as he plugged in his iPhone 4 in to charge.

An Apple spokesman said: ‘It was with great sadness we learned through press reports that a Beijing customer was injured while using a “knock off” or counterfeit charger and we are looking into this further.

‘Our customers’ safety is very important to us and we have carefully designed all Apple products to meet government safety standards. We recommend our customers only purchase Apple products from Apple or authorized Apple resellers.’