Hundreds of children in England and Wales were detained under the Mental Health Act and locked in police cells because officers did not have anywhere else to take them, the BBC has learned.
There were 305 detentions of under-18s in the first 11 months of 2013, Radio 4’s the World This Weekend found.
Some were held for more than 24 hours, according to data released under Freedom of Information laws.
The Department of Health said £25m was available to fund mental health nurses.
The practice of detaining children suspected of being mentally ill was first uncovered by the BBC in 2012.
Then, the data for 2011 showed there were 385 child detentions.
The latest information revealed that in 2012 there were 317 detentions.
See on www.bbc.co.uk