A 16-year-old girl with mental health issues, who was kept in police cells for two days, is being cared for on an adult psychiatric ward, it has emerged.
Devon Partnership Trust said the girl was being cared for "appropriately" until a children's bed could be found.
Paul Netherton, assistant chief constable at Devon and Cornwall, spoke out on behalf of the girl, who had been held in a Torquay police cell.
He said there had been no suitable bed available in the UK.
Mr Netherton raised concerns for the welfare of the teenager after she was arrested at Torbay Hospital and was later sectioned under the Mental Health Act.
NHS England said the 16-year-old was moved on Saturday night.
Health Secretary Jeremy Hunt told the House of Commons the case was not solved as quickly as it could have been due to "poor communication on the ground".
Liberal Democrat MP Adrian Sanders, for Torbay, said the case in his constituency was "outrageous", adding there had been 700 incidents of people in Devon and Cornwall with mental health problems being held in police cells this year.
Mr Hunt said: "It's totally unacceptable for someone with severe mental health problems to be placed in a police cell.
"In that particular case, there was a bed available but there was poor communication on the ground which is why we were not able to solve the problem as quickly as we could.
"But as soon as NHS England was informed about the problem they were able to find a bed, I think within about three hours.
"But you are absolutely right, this is a problem we must eliminate."
NHS England said in July the number of NHS-funded child and adolescent mental health services (CAHMS) beds for severe cases increased from 844 in 1999 to 1,128 in 2006, rising further to 1,264 in January this year.
But for England as a whole, a report said "it is impossible to conclude definitively whether the current level of bed provision is sufficient to meet the need".
NHS England found shortages in the South West and areas such as Yorkshire and Humber, resulting in patients being admitted to services a long way from home.
There are 23 CAMHS patients in beds across the South West.
NHS England said it was hoping to increase the number and was "developing enhanced community services" to help prevent admissions.
The reopening of Wessex House in Bridgwater, Somerset, last week would mean another 12 beds would be available by April 2015
Steve Sylvester, of NHS England, said: "These increases in capacity will help reduce the need for some patients to travel outside of the region and offer the opportunity for South West patients currently admitted outside the region to be treated closer to home."