The number of people who commit suicide after being released from police custody has hit its highest level for 10 years.
Figures released by watchdog the Independent Police Complaints Commission (IPCC) showed that 68 people apparently took their own lives within two days after being arrested or detained in England and Wales in 2013/14.
The youngest was aged 17 and another three were aged under 21.
While the number of deaths during or after police custody, which are treated separately to suicides, fell to 11, the body said that mental health issues "remain a serious concern".
A third of those who died in or after police custody, and two-thirds of those believed to have committed suicide, had mental health problems.
IPCC chairwoman Dame Anne Owers said: "Every loss of life is a tragedy. So, while we welcome the continuing fall in the number of deaths in or following police custody, the high incidence of mental health concerns among those who die during or after custody remains a serious concern.
"It is clearly important that the police are trained and supported to recognise and deal appropriately with those who are mentally ill. But they cannot do so alone.
"We welcome the steps being taken to pilot joint working across policing and mental health care, and will continue to ensure that the findings of our investigations into these tragic deaths inform better practice and improved service provision."
The IPCC investigated 39 other deaths following police contact, including five children - three babies aged under one and two teenage girls.
In total 19 of the deaths were related to domestic violence, of which there were 17 cases where victims were allegedly murdered by a current or ex-partner, or by a parent or parent's partner.
The remaining two were a 15-year-old girl who committed suicide after being sexually abused, and a friend of a domestic violence victim who was allegedly murdered.
In six of the non-domestic deaths, the person had been restrained by police before they died - two cases involved use of a Taser.
The IPCC figures, from April 2013 to March 2014, also revealed a sharp drop in the number of fatalities caused by road accidents.
Twelve people were killed in 11 road traffic accidents, nine of which were police pursuits, compared with 31 deaths the previous year.
Among those believed to have taken their own lives after being arrested or detained, 63 were men and five women, and half were aged 31 to 50. In total 65 were white, two black and one Asian.
The watchdog said that 32 deaths occurred on the day of release, 24 within a day and the remaining 12 within two days.
Some were arrested for minor offences, with nine being held for criminal damage or breach of the peace, and another nine for driving offences; although 13 were held for sex crimes, mostly suspected paedophiles.
The 11 people who died in custody were all men aged 31 to 70 - 10 white and one mixed race. Four had mental health problems.
They were arrested for various alleged crimes including three held for drug or alcohol-related crime, two for drink-driving, two detained under the Mental Health Act, two for theft or shoplifting, one for criminal damage and one for threats to kill.