An ambulance service where bullying was "normalised" and sexual misconduct cases were reported to police has been put in special measures by NHS England.
The Care Quality Commission (CQC) recommended the action after it found a "negative culture" and poor leadership at the East of England Ambulance Service NHS Trust (EEAST).
Former staff have spoken of a "toxic work environment" at the trust.
The trust said it was "taking urgent action to address challenges".
The CQC visited the trust, which serves Bedfordshire, Cambridgeshire, Essex, Hertfordshire, Norfolk and Suffolk, between 25 June and 15 July.
A string of failures were highlighted by inspectors in their report, including concerns over how the trust acted following allegations of serious offences made against employees.
The CQC said 13 cases of sexual misconduct and predatory behaviour, including claims of staff abusing patients, had been made to police between April 2019 and March 2020.
As a result of being placed in special measures, the trust will receive "enhanced support" consisting of an improvement director, a "Freedom to Speak Up" support package, "buddying" with other ambulance services and board development sessions.
Ann Radmore, NHS England's regional director, said although the trust "has been working through its many challenges, there are long-standing concerns around culture, leadership and governance, and it is important that the trust supports its staff to deliver the high-quality care that patients deserve".
A spokesman for the EEAST said: "We welcome the additional support announced today, which will help us to progress and sustain the improvements we want to make."