Interpol has issued a global alert to find missing five-year-old boy Ashya King.
Ashya was taken out of hospital in Southampton by his parents, who are then believed to have taken him to France.
ITV News correspondent Neil Connery tweeted:
#Ashya King - Interpol now issue a global alert as French police still work to establish his whereabouts.
Interpol said it had issued a "yellow notice" to all 190 member countries at the request of the UK authorities, and said all information coming in to its command centre in Lyon, France, was being treated as "high priority".
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.
The parents of Ashya King said they took him out of a hospital to seek proton beam treatment which is not available under the NHS.