Police in Lancashire are locking up the third highest number of children out of every force in the UK, shocking new figures reveal.
Research carried out by the Howard League for Penal Reform shows an average of 44 children aged 17 and under spent a night in the cells each week in 2011.
Only London and West Yorkshire had higher child detention rates.
The charity has criticised the practice of locking up youngsters, saying parents should take responsibility for their children.
But youth worker Dave Blacker, who works with youngsters in Blackpool, said the problem does not lie with the police.
He said: “I do think it is sad that the youth service is not a statutory obligation of local authorities.”
He said by making sure young people have access to the support they need, responsibility for keeping them safe will be taken away from police officers.
In 2011, there were 2,314 children locked up overnight in Lancashire.
For seven forces that figure was less than 100.
Mr Blacker added: “The police are fulfilling so many roles – sometimes they are having to act as almost a pseudo-social worker.”
He said often the decision to lock a child up overnight is taken with their own safety in mind.
But Frances Crook, chief executive of the Howard League for Penal Reform, said: “Holding children as young as 10 in police cells overnight is unjustifiable.
“The vast majority of children who are locked up are innocent of any crime, and it is a frightening and intimidating experience which does more harm than good.”
However, she welcomed the fact the child detention figures are falling.
Across the UK, the number of youngsters spending a night in the cells fell from 45,318 in 2010 to 40,716 in 2011.
Tim Ewen, Lancashire Police head of business support, said: “Taking someone into custody is a decision which is made by police officers on an individual basis for a variety of reasons, in accordance with the law.
“It is not a decision which is taken lightly – particularly when officers are dealing with young people.
“Lancashire Constabulary always aims to deal with anyone who is detained in our cells as quickly and efficiently as possible regardless of age and in fact the number of youths arrested in Lancashire is down by over 23 per cent over the past 12 months.”