Dutch teenager Charly T has been sentenced to 18 months in a juvenile prison and two months supervision by a Spanish court for a sexual assault on two British girls at a holiday park.

T, 17, was released from jail unexpectedly last week and is currently in the Netherlands. He does not yet have to return to Spain to sit out his sentence as long as it is unclear whether or not there will be a appeal, his lawyer told broadcaster NOS.

The Spanish public prosecutor had called for a four-year term for the assault on two sisters, aged 12 and 14 on the last day of their holiday.

The three met at the pool of a holiday resort on the Costa del Sol on the morning both he and the girls were leaving. They finished a bottle of vodka between them after which the alleged assaults took place.

T has always claimed to be innocent. NOS says there were no witnesses to the alleged events and police did not carry out a search. Minute amounts of the youth’s dna were found on the 12-year-old’s thigh.

PrisonLaw, an organisation which supports prisoners abroad, said earlier a conviction would be unsafe because there were no official interpreters present during the police investigation.