Ms McManus was transferred to Rochdale Infirmary but died of her injuries.

A 36-year-old male patient, Telahum Tedola, from the same ward has been charged with her murder.

Ms McManus's death comes months after the Healthcare Commission reported that mixed-sex psychiatric wards are common, despite government claims to the contrary.

A commission census of all mental health units in England and Wales found 55% of inpatients have to share sleeping accommodation or bathrooms with the opposite sex.

In July last year, Lord Warner, then health minister, told House of Lord peers that 99% of NHS trusts providing mental health services met "single-sex objectives" set out in 2000, requiring all mental health units to provide separate sleeping, toilet and bathing accommodation for men and women.

Campaigners say mixed-sex wards are highly unsuitable for psychiatric patients who may be extremely vulnerable.

At the time of the commission's census, Paul Farmer, chief executive of the mental health charity Mind, said: it was “quite staggering how bad the mixed sex wards situation is.”

"The NHS is putting some of the most vulnerable people in some of the most threatening and unpleasant environments,” he said.