Sexual harassment, racism, antisemitism and severe bullying have taken place at the state-funded German public broadcaster Deutsche Welle, staff members have told the Guardian.

Mid- and top-level managers ignored, targeted or silenced staff who spoke out, dismissing them or restricting their shifts, according to former and current staff members.

Deutsche Welle, which is financed by tax revenue, has around 1,500 employees and is comparable to the BBC World Service. It launched in 1953 and produces content on TV, radio and online in 30 languages.

“DW is a swamp,” one staff member said. “The irregularities are systemic: journalistic, political, ethical. There is no way to clean this system from within. The financier of DW, which is the German parliament, must take responsibility and investigate what’s happening.”

Examples of abusive behaviour cited by staff – most of whom said they did not want to be named for fear of reprisals – include:

In the Arabic division, a male colleague threatened to break a pregnant employee’s finger during a work shift in front of colleagues, staff have said.

At different locations at the Berlin offices at Voltastrasse, racial slurs relating to black, Jewish and Pakistani people are said to have been used openly to insult staff.

A black employee endured racist tropes about “eating fried chicken” and growing up in the “ghetto”, according to personnel. Staff describe the atmosphere at the broadcaster as feeling “like a prison”.

The alleged incidents took place in 2018.

Last year, Die Zeit reported that a star presenter at Deutsche Welle’s Arabic service had resigned in 2018, citing exhaustion, following accusations against him of rape and sexual harassment. The presenter denies the allegations. His lawyer told Die Zeit that his client “would like to repeat that he never molested anyone or would molest them. He never had and would never force anyone to do anything against his or her will.” He did not respond to a request for comment from the Guardian.

Staff at the channel say a leaving party attended by managers was held for the presenter, even after the rape allegations had come to their attention. Before the party, staff were called to a meeting and threatened with legal action if they spoke about the accusations against him, they say.

A group of 20 employees filed a letter of grievance to management, they say. A senior manager within the department followed this up with meetings where he reportedly called the signatories “traitors and saboteurs,” claiming the letter was “treasonous” and “backstabbing”, according to staff. The manager did not respond to a request for comment from the Guardian.

George Walden, a contracted journalist at Deutsche Welle, described other examples of racism and bullying in a letter to DW management seen by the Guardian. He claimed that another presenter was verbally abusive to staff, and was only forced to leave, in 2018, after Walden brought the issue to senior managers and threatened to speak to the media about the issue. Another staff member claims 15 other complaints against this presenter were not examined.

“On my first day, there was an intern sitting at the desk, and the presenter turned to the intern and said ‘why the fuck are you sitting there’ and ‘get the fuck out of my seat’ with management present,” Walden said. “It was absolute chaos.”

This presenter, who was appointed to train Walden, “constantly abused me with verbal threats, F-bombs, and berated me in public for just asking questions concerning what I was there to learn,” said Walden. “He thrived on an air of intimidation which you [the network] allowed to happen in the workplace.”

He and other members of staff accused the presenter of being antisemitic. Some said the presenter would target colleagues he believed to be Jewish arbitrarily, using antisemitic insults in the open office.

“From what I witnessed, it seemed to build up over time as he targeted certain colleagues,” one staff member said. “He would just use the term as shorthand. ‘Oh, yeah, that fucking Jew over there’.”

Asked about the allegations, the presenter declined to comment.

Other staff claimed to have overheard the use of the N-word at Deutsche Welle and routine use of racist and sexist comments.

“There were just so many incidents,” one member of staff said. “So I just kind of got the impression that this is the way it is, it’s like a very male-dominated environment, where [it still feels like] you live in the 1950s and 60s, in terms of the language used […] the sort of sexism, racism.”

Deutsche Welle claims it is addressing structural problems relating to the allegations. “We wanted it to be clear there would be a zero tolerance policy particularly regarding sexual abuse,” said a Deutsche Welle spokesman, Christoph Jumpelt. “We made an effort to enter into conversation with people in the individual editorial and all other departments. We made the subject a top priority. We invited everyone to talk about having zero tolerance not only regarding sexual harassment but to any abuse of power. We followed up every allegation that was made, some of which were critical and serious.”

Jumpelt added: “But we are aware and need to be careful that it doesn’t lead to a campaign which colleagues use as an excuse for personal vendettas against each other. We are in a German legal context, and to be honest, first you have to prove that there’s something to an allegation. False allegations can easily be made. We cannot terminate contracts on the basis of allegations. We need to prove it and make sure there is a fair process.”

Deutsche Welle denies the party was held for the presenter accused of rape, saying it was to “mark the conclusion of production of that particular show”.

“It was a wrap-up party after two and a half years for that show, not a farewell party to anybody,” Jumpelt said. At the party, “the presenter and his team were thanked for their work because they had done good work”.

Asked about the presenter accused of using antisemitic insults, Jumpelt said: “We cannot comment on individual cases due to the protection of personal rights. We can only say that the freelancer mentioned no longer works for us. Our HR department makes use of the full range of labour law tools, including warning letters and termination without notice, if necessary. In cases when we conclude that we may be faced with a serious problem, we initiate an intensive dialogue and workshops with the department, highlighting the importance of a respectful and appreciative working environment and raising employee awareness of all forms of potential misconduct. This is what we have initiated in the sports section.”

Jumpelt said the company had implemented workshops to address what they claim are isolated incidents of interpersonal conflict, but staff claim the management team has repeatedly overlooked abuses of power.

“To be honest in a big organisation like ours – with 3,000 workers, 1,500 of them on fixed-term [staff] contracts, the others on freelance employee contracts from 60 different nations – problems can happen, but we are dealing with all of them,” Jumpelt said.

Ver.di, the union representing media workers, told the Guardian that staff who had reported abusive behaviour had suffered reprisals.

“Sadly we had to discover that colleagues who came forward and revealed abusive behaviour, now are being disparaged and intimidated,” a spokesperson said. “In one particular case, this led to one colleague’s termination.”

The union spokesperson added: “At least one editorial department is ruled by a climate of fear.”

• This article was amended on 20 January 2020 to more accurately describe some of the locations where racist incidents were alleged to have occurred. It was further amended on 24 January 2020 to clarify that the matters referred to in this report were alleged to have taken place in 2018 and to remove a description of the management team as “all-white, all male”.