1: What are UK rules on vaping?

Vapes or e-cigarettes don't contain the harmful tobacco present in normal cigarettes, but they do contain nicotine - the substance which makes people addicted to smoking.

They are growing in popularity as an aid for quitting smoking, along with other nicotine replacement products like patches or gum.

The Department of Health and Social Care in England says that while they're not risk-free, UK-regulated vapes are far less harmful than smoked tobacco. But it continues to strongly discourage non-smokers and children from using them.

UK laws limit how much nicotine and e-liquid is allowed, and health warnings are required on packaging.

However, large numbers of vapes which are not designed for the UK market, are being smuggled into the country.

"There's no way of knowing what's in them," said Helen Donegan, senior trading standards officer with Leicestershire County Council, who told the BBC that 8,000 illegal vapes had been found at one premises alone.

"They are making them extremely attractive to young people - but they could be inhaling a banned substance."

Some look very similar to big-name vape brands, but are fake - others contain illegal amounts of nicotine and e-liquid.