Why Tesla has been caught up in a massive car recall in China

Hidden car door handles - the sleek designs often found on electric vehicles (EVs) - have come under the spotlight over the past week.

That's after China announced its biggest ever recall of cars, with more than four million vehicles - mostly Teslas - affected .

The recall comes ahead of new regulations in China , requiring cars to have a mechanical release both on the inside and outside of their doors.

Popularised by Elon Musk's electric vehicle giant, this type of handle has become commonplace around the world.

But several incidents have raised concerns that this design may make doors difficult to open in an emergency.

Hidden door handles are widely used in modern cars in China, with around 60% of the top 100 best-selling new energy vehicles, including EVs and hybrids, having them.

The minimalist design gives vehicles a "sleek look and reduces wind drag" but can be confusing to use, car industry analyst Stephen Dyer from consultancy AlixPartners told the BBC.

"Even I often find it difficult to locate the switch to open the door from the inside of an unfamiliar vehicle," said Dyer, who is based in Shanghai.