A lack of beds is forcing mental health patients in England to seek treatment in other NHS facilities up to hundreds of miles away, BBC research has found.
The number of patients travelling to seek emergency treatment has more than doubled in two years - from 1,301 people in 2011-12 to 3,024 in 2013-14.
Earlier this year one patient was admitted to a deaf unit as no beds were available anywhere in the country.
Health minister Norman Lamb said out-of-area treatment was a "last resort".
The care and support minister added that it was "unacceptable" if patients had to travel "hundreds of miles" for treatment and said he was determined to drive up standards of care in the NHS.
Leading charities have called the situation scandalous and a disgrace.
One mental health trust spent £345,000 last year placing patients in bed-and-breakfast accommodation in order to free up much-needed beds.
Mental health trusts are having to cope with cuts of more than 1,700 beds over the past two years, and the problems in the system have come to light following a joint investigation between BBC News and the online journal Community Care.
Sending patients out of area can be appropriate for specialist treatments.
Figures obtained as part of the investigation, through Freedom of Information requests, show some trusts are managing to maintain, or even reduce, the number of people they send elsewhere.
But the data from 30 of England's 58 mental health trusts shows that overall the number of patients sent out of area has more than doubled between 2011-12 and 2013-14.
The increase comes despite the number of patients being admitted to hospital for mental health problems falling slightly from 167,285 in 2011-12 to 166,654 in 2012-13.
Kent and Sussex are among the worst-affected areas. In Kent 334 patients were sent out of the county last year at a cost of £5m, compared with just 20 people in 2011-12, at a cost of £141,000.
One patient complained she was made to sleep on a mattress on the floor due to the lack of beds. The trust said there was unprecedented demand for beds last year.
In Sussex, the number of patients sent out of area increased from 28 in 2011-12 to 227 last year.
Lisa Rodrigues, chief executive of the Sussex Partnership NHS Foundation Trust, said rising demand for mental health services and cuts to community services by councils were creating problems.
She said: "Mental health services are a barometer of how the system is operating and if you remove some of the lower levels of support that people rely on to maintain their lives, it's not surprising that they'll present in crisis.
"We are seeing people coming to hospital who are much, much iller when they arrive so we have higher numbers of detained patients but, much more than that, we're seeing people have to stay in hospital for longer."
Difficult to cope
One patient who knows what it's like to be transported far from home is "Alison" (not her real name).
The 32-year-old from York, who suffers from bipolar disorder, was taken to a hospital in London, 200 miles (320km) away, in the middle of the night when health officials couldn't find a bed for her closer to home.
Though she praises her treatment, she says it was a "shock to the system" and the distance was difficult to cope with.
"With me not being near friends and family I suffered, I had anxiety, I wanted to speak to people and have familiarity around me," she said.
Other patients have had to travel even further, with people being sent from Devon to West Yorkshire (300 miles), and Oxford to Teesside (240 miles).
A London trust - Barnet, Enfield and Haringey - has been reprimanded by the regulator, the Care Quality Commission (CQC), for using seclusion units as bedrooms.
It also started to move patients out of beds and into bed-and-breakfast accommodation. The figures show that 132 people were sent to B&Bs last year.
The trust said the patients were fit to be discharged from hospital but had accommodation problems - however, it admitted it was not ideal for patients.
A board meeting of the Birmingham and Solihull trust in January heard a complaint from a patient who was admitted to a deaf ward despite not being deaf, which she says made her feel stressed and unable to communicate with staff and patients.
An investigation by the trust found this had happened because there were no female beds available in the country. Procedures have now been changed, the trust says, which should ensure it never happens again.
'Fend for themselves'
Marjorie Wallace of the mental health charity SANE said: "This situation is a result of the longstanding agenda to reduce the number of psychiatric beds, the most expensive element of care. But this is a false economy - leading to misery for many who struggle to access the treatment they need and undermining their chances for recovery."
Paul Farmer, chief executive of mental health charity Mind, said: "It is a disgrace that people with mental health problems are being sent miles away from family and friends or being accommodated in inappropriate settings when they are acutely unwell.
"This is the latest in a long line of clear signals that, at least in some parts of the country, NHS mental health services are in crisis. Continued cuts to funding for mental health services are taking a significant toll on the quality and availability of services."
Mark Winstanley, chief executive of Rethink Mental Illness, added: "It's absolutely scandalous that people with serious mental health problems are being treated in such a terrible way.
"Anyone going through a mental health crisis should expect to get help in a therapeutic environment where they can get better.
"The last thing they need is to be shunted to a hospital hundreds of miles away or, even worse, left to fend for themselves in a bed and breakfast."
Karen Wolton, a member of the Mental Health Lawyers Association, commented: "We've noticed a sharp increase in the last year with inappropriate admissions for out-of-area beds. We've had people admitted from where they live in Margate to Weston-Super-Mare which is a trip of 225 miles.
"We've had people overdosing in order to obtain a bed. They've told us that they deliberately overdosed because that's the only way to get a bed.
"We've also had people who are inappropriately discharged after long spells in psychiatric hospitals; they're being discharged to bed and breakfast accommodation."
Mr Lamb admitted there was an "institutional bias against mental health" in regard to waiting-time targets.
"When the 18-week maximum waiting time was established in the last decade it applied only to physical health," he told the BBC.
"That left out mental health and incredibly, politically significant targets of that sort dictate where the money goes."
The situation "has to change," he added.
But Labour's public health spokeswoman Luciana Berger said mental health services were "suffering from repeated government budget cuts".
"Under David Cameron, wards are operating beyond safe occupancy levels and patients are turned away," she said.
"Ministers must ensure that mental health services are accessible. They claim to support parity of esteem between mental and physical health but patients are being badly let down."