The Home Office has reportedly suspended an immigration official and ex-Metropolitan Police officer after a BBC investigation alleged he had been posting racist content on WhatsApp.
The BBC programme Newsnight said it was shown messages from the group by Dave Eden, another former police officer.
The Home Office said it had suspended a member of staff following allegations of gross misconduct.
“These messages are vile and deplorable. We expect the highest standards of our staff and have a zero tolerance approach to anyone displaying racist, homophobic, misogynist or discriminatory behaviour,” the statement said.
“Where we are made aware of such behaviour we will not hesitate to take decisive action.”
Commander Jon Savell, who is responsible for the Metropolitan Police’s professional standards, said the messages shared were “abhorrent”.
“These messages are abhorrent and have absolutely no place in policing or society,” he said.
“Their behaviour erodes the confidence that the public has in the police – a confidence that the vast majority of us in the Met works tirelessly day-in, day-out to maintain and improve.
“Racism, misogyny, homophobia or any other discriminatory behaviour has no place in the Met.
“Where such behaviour is identified it will be dealt with robustly, but we will also be actively seeking out those whose actions bring shame to us.
“We contacted Mr Eden’s representatives when these messages first emerged in April but they declined to share further details. We urge them to reconsider so we can take action.
“In the meantime we appeal to anyone who has information about such behaviour to make contact.”
Commissioner Sir Mark Rowley added: “My plan for reform in the Met is already under way. I will be ruthless in rooting out those corrupting officers and staff, including racists and misogynists, from our organisation.
“I have taken over as the leader of an organisation that has been far too weak in taking on those who undermine the honest and dedicated majority who determinedly serve the public.
“That will change and I will continue to seek out those, from both within and outside the Met, with that constructive anger who can help us reform.”
The Mayor of London, Sadiq Khan, described the message in the group as “abhorrent” and said those involved should be held to account.
He said: “The Met has previously been far too weak and slow to act when this kind of unacceptable behaviour has been exposed. The new Commissioner, Sir Mark Rowley, has assured me that he’s determined to take a different approach. Any officers found to be responsible for sexism, racism, misogyny, homophobia, bullying or harassment do not deserve to wear the Met uniform and must be quickly rooted out.
“Baroness Casey continues to lead an independent review into the Met’s culture and standards, which will be vital in helping us to deliver the widescale police reform that’s clearly required.
“Sir Mark Rowley has committed to winning back the trust of Londoners in the police and I’m confident he understands the scale and urgency of the task at hand. I want to assure Londoners that I will continue to hold the Met to account to ensure we see the step change in culture and performance that’s urgently needed, and which Londoners deserve.”