"To assume that just because of someone's age and gender that they don't pose a threat would be misguided and wrong."
The boy is a US citizen. His mother is of Iranian origin.
Footage shows the boy's mother waiting anxiously at Dulles International airport in Washington DC before being reunited with her son, who was reportedly flown into the airport with another family.
She then sang "happy birthday" to the little boy in English as she hugged him and covered him with kisses as onlookers cheered.
White House claims five-year-old boy detained in US airport for hours 'could have posed a security threat' [Rachel Roberts/The Independent]