Three missing people have been reunited with their families in time for Christmas after their faces were displayed on posters on the backpacks of Deliveroo riders.
Five hundred of the food delivery app's riders will sport mobile billboards in London, Manchester, Birmingham and Bristol from Monday as part of a campaign with charity Missing People.
A trial across the four cities has already yielded results, with three out of the four people featured being found safe and well.
The full roll-out of the "Ride to Find" campaign will see riders display posters featuring a total of eight - two in each city - missing people on the bags used to carry food.
Likened to advertisements on milk cartons used to trace missing children in the United States, the initiative will run throughout December.
Jo Youle, Missing People's chief executive, said: "We hope this fantastic partnership will help us reunite families and loved ones this Christmas."
The Deliveroo app is also introducing a fundraising feature, giving customers the opportunity to donate to the charity.
Each of the firm's 15,000 riders will be encouraged to sign up to receive child rescue alerts, which notifies subscribers whenever a missing child in their area is considered to be at a very high risk of harm.
The company's chief executive Will Shu said: "It's with great pride and purpose that we rollout our national initiative to support Missing People's incredible work.
"For those affected, the support and actions of Missing People can be live saving. When we had the opportunity to meet with them, we knew instantly that we wanted to help.
"Our riders are at the heart of our business and are seen by communities up and down the country as they travel our streets to deliver food.
"It's amazing that our network has volunteered to use our recognisable backpacks to create mobile billboards in support for such an important cause.
"We hope that over the holidays, our Ride to Find campaign will help bring missing people home to their friends and family as well as raise awareness and funding for the Missing People charity."
Ms Youle added: "We are thrilled to see the forward-thinking and innovative Ride to Find campaign go live.
"Deliveroo will help us to reunite missing people with their families this December and will be able reach people and places Missing People cannot.
"We ask the public to be extra vigilant to assist us and Deliveroo in our attempts to resolve as many cases as we can in the run up to Christmas.
"The money raised by Deliveroo and their customers will help us to continue to search across the UK for missing people and support the estimated one million people who are affected by a disappearance.
"For families who have a missing loved one, life can feel like a desperate and unbearable struggle and Christmas is a particularly difficult time."
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