An Essex mental health trust is facing allegations of staff supplying illicit drugs to and engaging in sexual activity with vulnerable patients.

The claims against Essex Partnership University NHS foundation Trust (EPUT) were uncovered by the BBC and will be laid bare in its Radio 4 File on 4 programme from 8pm tonight.

EPUT has launched its own inquiry into allegations made and has set up a helpline for patients and relatives affected by the issues raised.

The EADT has spoken to two mothers who are campaigning for change at EPUT.

Melanie Leahy claims staff failed to follow policy after her late son, Matthew, reported being drugged and raped while he was a patient in 2012, putting it down to delusions as a result of his illness. He was found hanged just four days later.

The Parliamentary and Health Service Ombudsman is investigating, she added.

Mrs Leahy, of Tolleshunt Knights, said she was aware of illicit drugs being delivered to patients through the window of an EPUT unit.

She added: “There needs to be more thorough, rigorous checks on staff that are being employed there or coming in through agency doors and really tightening their security.”

Another mother, who asked to remain anonymous, told the EADT how her daughter had been groomed and had received sexually explicit messages from EPUT staff while she was a patient.

The woman said her daughter had also been offered illicit drugs during her stay.

A spokeswoman for EPUT said she could not comment on individual cases due to patient confidentiality.

She added: “We take concerns raised with us seriously and they are investigated as safeguarding incidents and reported to the police, if appropriate.

“As soon as the BBC brought an allegation to our attention, we opened a formal investigation. We have requested further details from BBC in order to progress this investigation, however, to date they have not provided these.”

EPUT took over from two former trusts in April 2017.

The spokeswoman said: “The new trust takes full responsibility for what has happened in the past, learning the lessons and taking action.

“From day one, our top priority has been to improve patient safety continuously. We are committed to doing all we can to put things right, wherever possible, by taking a very open approach and empowering our staff to make the changes needed. Some changes have been implemented immediately; others will take more time to see through.”

Patients and family members wanting to contact the EPUT helpline can do so by calling 01268 739182.