Social Bite will expand its charity sleepouts around Scotland this year.

Mass sleepouts are due to take place in Edinburgh, Glasgow, Aberdeen and Dundee on December 8.

The sandwich shop chain is aiming to attract 12,000 participants for this year's Sleep in the Park, who will raise cash by sleeping outside in the cold.

Amy MacDonald and KT Tunstall will perform at all four events, travelling by helicopter to each location.

Trainspotting author Irvine Welsh will read a "bed time story" at the event, which hopes to raise £6m.

In December last year, around 8000 people took part in the Sleep in the Park fundraising event, in what was billed as the world's largest sleepout.

Celebrities including John Cleese, Rob Brydon and Sir Bob Geldof providing entertainment to those braving the elements.

Social Bite said £3.6m was raised to help rough sleepers find accommodation.

Social Bite co-founder Josh Littlejohn said: "For Sleep in the Park 2018 we're doing something that has never been done before - a simultaneous multi-city sleep out.

"We're asking for 12,000 people in Edinburgh, Glasgow, Aberdeen and Dundee to keep the momentum going and raise £6m.

"We were completely blown away by the thousands of people who joined this movement and supported Sleep in the Park last year. We want to build on this across the whole of Scotland.

"By organising these events locally, we will invest the funds so that homeless people in those cities are housed and given the support they need to get back on their feet."

He added: "The money raised from Sleep in the Park 2018 will be put towards rapidly rehousing rough sleepers and providing them with support.

"We'll make sure that the most vulnerable members of society - for example people coming from the care system or prison - don't end up homeless.

"The funds will also go towards a number of other programs that will be a catalyst for long-term structural change.

"By collaborating, and treating homelessness as a political priority, I believe that Scotland can be a country where everyone has a place to call home."

This year has also seen the launch of Social Bite's new, purpose-made village in Edinburgh which offers accommodation to homeless people.

Social Bite was also visited by Prince Harry and Meghan Markle during their first trip to Edinburgh.