A family who took a boy with a brain tumour from hospital yesterday arrived in France at 8pm local time last night, police said.
Hampshire Constabulary 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 King's parents told the Daily Mail they fled the UK after being told NHS treatments would leave him with life-long disabilities.
The head of the police force which applied for a European Arrest warrant against the parents of Ashya King has now urged their release.
A British mother whose son's life was saved by proton therapy has told ITV that she defied NHS doctors' advice to pursue the treatment.