Police in Hampshire have launched an "urgent" appeal after a five-year-old boy suffering from a brain tumour was taken from a hospital by his parents.
Ashya King was removed from Southampton General Hospital without doctors' knowledge by his parents Brett King and Naghemeh King.
The family then boarded a cross-Channel ferry from Portsmouth to Cherbourg and arrived last night (28 August) at around 8pm local time.
Hampshire Constabulary said there are "serious concerns" for the life of a five-year-old as he requires constant medical attention and needs to be taken to a medical facility as soon as possible.
Ashya's six siblings are also travelling with the family.
Detective Superintendent Dick Pearson, of the Hampshire Major Investigation Team, said: "He needs to be taken to a medical facility for his urgent health requirements as soon as he is located.
"We have also launched a social media appeal and would urge everyone to share this appeal, particularly if you have friends and relatives in France and bordering countries."
Police have released images of Ashya and his parents as part of the appeal. They have also released CCTV images of King taking his son out of the hospital.
A Hampshire Constabulary spokesperson said: "We are working with our counterparts in France to activate their emergency child rescue alert procedures to locate the family as soon as possible. If we do not locate Ashya today there are serious concerns for his life.
"He is receiving constant medical care within the UK due to recent surgery and ongoing medical issues. Without this specialist 24-hour care Ashya is at risk of additional health complications which place him at substantial risk."
Police said the family are travelling in a grey-coloured Hyundai I800 Style CRDI, registration KP60 HWK, and they are still believed to be in France.
Ashya is likely to be in a wheelchair or buggy, he cannot communicate verbally and is immobile, a police spokesman added.