Unaccompanied children who arrive in the UK at Dover could be held in protective custody to stop trafficking, under Kent County Council (KCC) plans.
Last year 26 out of 105 unaccompanied minors went missing, KCC said.
Councillor Jenny Whittle, KCC children's services spokeswoman, said they could be held for up to six weeks before being moved to foster care.
The Children's Society said placing children in custody could make them feel further victimised.
'Window of opportunity'
Ms Whittle said not all children who went missing were trafficked but she said a quarter of unaccompanied minors went missing last year.
Out of those, two-thirds were from countries such as Vietnam and China where there was a high suspicion of trafficking, she added.
She said she was seeking to draw up plans for secure accommodation where children would have access to legal independent advocates.
The facility would allow staff to capture "a window of opportunity", which was the first four to six weeks after a vulnerable child had entered the port - the time when most children went missing, she added.
She said: "I would rather keep them in protective custody and secure accommodation for four to six weeks than see the children disappear into the hands of traffickers and end up in a life of being raped on a daily basis, or growing cannabis in factories, or being in domestic servitude."
Ms Whittle said unaccompanied minors could currently leave their accommodation at any time, and added: "Some of them are fleeing into the hands of traffickers and I've got to find a solution."
'Detrimental impact'
Ilona Pinter, policy adviser on young refugees and migrants at the Children's Society, said: "Our experience, and the things that children tell us, is that detention has a very detrimental impact on their well-being and a lasting impact."
Ms Pinter also said children could go missing for other reasons, such as fear they might be returned to their country of origin.
She said: "Two years ago the government was talking about returning minors to Afghanistan.
"When this came out in public and through the media there was a great panic and we worked with the young people that we provide advocacy and support to, to keep them safe, to help them understand what can happen to them and what the asylum process is.
"What we really need to do is put in place legal independent advocates who can build that relationship right from the beginning with children, because I think if you put children even in protective custody you risk making them feel further victimised."
bbc.co.uk
