Ashya King's father said he was "treated like a criminal" by Border Force staff when he arrived back in the UK.
An angry Brett King, whose son Ashya is a brain cancer sufferer, confronted police at London's Gatwick Airport after being stopped at passport control with his other son Naveed.
He told officers: "How would you feel, coming back into your own country and you are treated like a criminal?
"What have I done except help my son?"
The confrontation is shown in an undated camera phone video posted on YouTube by Naveed this afternoon. Words: PA
It starts with Mr King sitting in a holding area at passport control as he tells how the two of them had their passports seized when they arrived and were asked to wait in a holding area.
After a policeman calmly tells Mr King he cannot see the computer information about them - but will not be arrested - he storms off, followed by his son.
Mr King and his wife Naghmeh sparked an international manhunt when they removed five-year-old Ashya from Southampton General Hospital on August 28 without medical consent.
Their son has now completed a course of treatment at the Proton Therapy Centre (PTC) in Prague and is now recuperating with the family in Spain.
He adds: "But already, on my first attempt to come back to England ... I'm having problems."
A Home Office spokesman said: "We do not routinely comment on individual cases."
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