Ashya King, who is undergoing his first tests at a Czech clinic in preparation for proton treatment, could have a 70% chance of survival, doctors said.

Ashya King will make his first visit today to the Czech clinic where he is expected to receive the treatment that prompted the legal wrangle over his care.

As Ashya King’s parents were reunited with their son in a Spanish hospital yesterday after being released from prison on Tuesday, they claimed they had been treated like terrorists.

The grandmother of brain tumour patient Ashya King said she was “relieved” his parents had been released from a Spanish prison but the authorities in the UK needed to be held to account.

The council that began legal action after brain tumour patient Ashya King was removed from hospital without his doctors’ consent has joined mounting calls for extradition proceedings against his parents to be dropped.

The parents of five-year-old brain cancer patient Ashya King have spent another night away from their son as relatives and supporters continued to demand their release from detention.