After a Chinese woman was earlier this month evidently electrocuted while talking on her iPhone
while it was plugged in to charge, Apple is warning users to avoid counterfeit chargers. From CNet:
"Last week, reports surfaced in China that suggested the woman, Ma Ailun, might have been using a third-party charger designed to look like the real thing. Although third-party chargers are not uncommon, they vary widely in terms of safety and quality.
Earlier this year, safety consulting and certification company UL issued a warning that counterfeit Apple USB chargers were making the rounds and that consumers should be on the lookout for them due to their lower quality and possibly dangerous defects. The company posted the guidance on its site after a woman was allegedly electrocuted while answering a call on her iPhone."