Police cells should stop being used to detain mentally ill people, a police body has said, with one minister calling the issue a "national scandal".
A chief superintendent has called for mentally ill people to be taken to A&E if mental health services are unable to take patients dealt with by police.
The Association of Chief Police Officers estimates that about 20% of police time is taken up dealing with people who are mentally unwell.
Chief Superintendent Irene Curtis told BBC Panorama police cells are inappropriate places for people who are suffering a mental health crisis, and it takes officers away from core police work.
She said: "I think as long as there is an option that to have a police station as a back-up then they will always be used... You get to the stage where you actually say no, enough is enough... police cells should stop being used.
"If there are no spaces at the mental health unit, then my belief is that an accident or emergency unit at a local hospital must be a better place than a police station."
She said that it is becoming a "national issue", especially as budget cuts kick in.
Norman Lamb, minister for care and support, agreed that it was time for change.
"The very worst place for someone with a mental health problem to be seems to me is a police cell," he told Panorama.
"Some of the care that is received by people in a moment of crisis in mental health is, frankly, unacceptable. It's a national scandal that needs to be addressed."
But he believes shifting responsibility from the police to mental health services is "not the right way" to cope with the situation.
"It shouldn't be about police just saying we're just going to take them, march them into and A&E department and abdicate our responsibility," he told Panorama.
"That's not the right way.
"It should be police together with mental health, reaching a conclusion about what is in that patient's best interests," he said.
Panorama: Locked Up For Being Ill? will be shown tonight at 8.30pm on BBC One.