The Metropolitan police have denied the force is plagued by a culture of misogyny after an official report revealed shocking details of officers sharing messages about hitting and raping women, as well as the deaths of black babies and the Holocaust.

The officers were based mainly at the Charing Cross police station in central London, with the offending behaviour taking place between 2016 and 2018.

The home secretary, Priti Patel, singled out the culture in the Met as an enduring problem, with a government source telling the Guardian: “We’re not letting them off the hook on this,” amid women’s groups concerns that is exactly what will happen.

The conduct, including messages about violence against the public, amounted to bullying and harassment, the Independent Office for Police Conduct (IOPC) watchdog found.

The messages were shared among a group of up to 19 officers, with the hateful and offensive remarks part of a Met culture that needed to be rooted out, the IOPC said, with fear stifling whistleblowing and officers believing bosses would not take it seriously or protect them from reprisals.

The home secretary has already ordered an inquiry chaired by Dame Elish Angiolini after a Met officer used his police powers to kidnap, rape and murder Sarah Everard.

Patel said: “It has been clear for some time that there are problems with the culture of the Metropolitan police, which is why last year I tasked the Angiolini inquiry and the police inspectorate with investigating these deeply concerning issues.”

But the home secretary is facing legal action to force a tougher inquiry, with women’s groups and experts pointing to case after case where women suffer at the hand of the police who are supposed to protect them.

The Centre for Women’s Justice wants the government inquiry to be empowered to compel evidence and to hunt out the deeper reasons, such as alleged misogyny, for repeated scandals.

Dabaleena Dasgupta of the CWJ said: “It must examine the wider issues why these cases keep happening, which we believe is rooted in misogyny in the police. Charing Cross is just the latest example of this”

The IOPC released extensive and shocking details of the messages shared by the Met officers via WhatsApp or Facebook . Examples of the offensive messages included:

• One male officer wrote to a female officer: “I would happily rape you … if I was single … if I was single I would happily chloroform you.”
• Another officer advocated violence: “Getting a woman into bed is like spreading butter. It can be done with a bit of effort using a credit card, but it’s quicker and easier just to use a knife.”
• Police officers wrote about attending a festival dressed as known sex offenders and a molested child.
• “Numerous messages about rape and ‘raping’ each other” were sent in two WhatsApp group and one Facebook group.
• One officer messaged another saying he was going to attack his partner and wrote: “Swear to got [sic] I’m going to smack her”.
• Another message shows an officer bragging about visiting a sex worker when he was using steroids.

The Met denied misogyny was a factor and a spokesperson said: “We do not believe there is a culture of misogyny in the Met. There are a number of recommendations in the report that we will consider before formally replying to the IOPC.”

A spokesperson added the Met is “an organisation of more than 44,000 people; there will be a small number with attitudes and beliefs that are not welcome in the Met; we will challenge, educate and discipline as appropriate.”

The IOPC said those officers who knew about the messages had been afraid to challenge or report it, and those who did were “harassed, humiliated and excluded. Challenging sexual harassment led to additional problems.

“Female officers told us they would be treated as the ‘weary female’, told it was part of police culture, that they should accept, ‘play the game or stay quiet’, or leave. We also obtained evidence that reports of sexual harassment were not dealt with sensitively within the MPS [Metropolitan police service].”

Messages sent between the officers threatened those who were thinking about breaking the silence, including: “There’s a few of those grassing c***s I would like to knife.”

The IOPC said the messages showed attitudes that left ethnic minority and female staff in fear and could show officers being discriminatory to their colleagues and staff. The officers also shared a series of racist messages.

These included: “PWPEHCLM – People with pre-existing heart conditions lives matter. Should of offered him a KitKat and a nice lie down. Murdering cunts” and “Bring all the lefties I say, we can sing ‘cum by ya’ and embrace our multi gender/ethnic and sexual backgrounds whilst denouncing all the fascists in the MET.”

There were also messages containing abuse against Muslims and disabled people.

The IOPC said the behaviour was part of an offensive Met police culture, not just rogue individuals. “We believe these incidents are not isolated or simply the behaviour of a few ‘bad apples’.”

The watchdog added: “The culture of bullying appears to have been accepted and not challenged. A reason for not reporting such behaviour was a lack of confidence that it would be dealt with effectively and fear of repercussions. In one case, allegations of bullying were not dealt with effectively or promptly by the supervisor who was in a relationship with the person making the allegations.”

Of 14 officers investigated, two were sacked for gross misconduct, Misconduct was proven against another two, with one officer receiving a written warning, while another four faced measures to improve their performance.

Bas Javid, a deputy assistant commissioner with the Met, said he was “angry and disappointed”, felt “disgust and shame” and added “It’s clear we have a lot of work to do to ensure bullying and discrimination does not exist in any part of the Met.

“We recognise that there is need for real change in the Met.”

The IOPC said it reviewed thousands of messages and some officers tried to defend them claiming that they were “banter”, an excuse that was not accepted.

Sal Naseem of the IOPC said: “The relationship between the police and the public is critical to maintaining the principle of policing by consent. The concerns about behaviour and culture addressed in our report, if allowed to continue and go unchallenged, risked causing serious damage to that relationship.”

With confidence in the Met faltering, the London mayor, Sadiq Khan, said: “What has been revealed by these investigations will only further damage public trust and confidence in the police.”

Ruth Davison, the chief executive of Refuge, said: “Not only have the Metropolitan police again been found using horrific, misogynistic language, some officers appear to be bragging about committing domestic abuse themselves.

“Strong action must be taken and the police must rid itself of its culture of violent misogyny.”