Ten adults and 11 children as young as 12 have been found hidden inside a refrigerated lorry entering the UK.

The group, who said they were from Vietnam, were concealed in a shipment of sparkling water at the port of Newhaven in East Sussex last Thursday, according to the Home Office, which said the lorry was stopped after arriving from the French port of Dieppe.

After being discovered by agents from the Border Force, 17 of the group initially claimed to be minors. Interviews and age assessments later established that 11 were aged under 18.

Two of the adults – a man aged 18 and a woman aged 27 – were expelled from the UK, while the remaining eight – four women and four men – must now report regularly to Home Office immigration centres while their cases are examined. The children were placed in the care of social services. They were cold but did not need medical treatment, the BBC reported.

A criminal investigation into the circumstances of their arrival was under way.

A Romanian man believed to be the driver was arrested and charged with assisting unlawful entry to the UK. Andrut Mihai Duma, 29, of no fixed UK address, was being held in custody until a hearing at Lewes crown court on 26 November.

The case is being led by Immigration Enforcement Criminal and Financial Investigations.