A university "confessions" page has closed amid a police investigation into coded racist posts.
References to Adolf Hitler and white supremacy were made in posts on the ExeHonestly Facebook page.
Administrators for the unofficial Exeter University page said the messages had "slipped" past its moderators.
They said in the "last ExeHonestly post ever" that they "did not sign up to hurt anyone or become hunted".
ExeHonestly is one of more than 100 Facebook pages around the country which allow students to post messages anonymously.
One of the offending posts, since removed, included the number 88 - said to be code for "Heil Hitler", while another promised users "a bag of sweeties" if they could solve a riddle.
The question: "What accounts for 15%, yet 32%?" references a disputed statistic relating to the number of crimes committed by African Americans.
Exehonestly administrators said the true meaning" of the "dog-whistle" posts was "not apparent to people unless they have specialised knowledge".
But the university responded saying it was "not credible" that admins missed the racist messages.
It said a "ten second internet search would have indicated that the latest posts were offensive".
It added that "to claim ignorance about posting offensive content on multiple occasions is either not credible or is evidence that they are not capable of hosting a community site".
Administrators said in a final post on the page that the university's response was "unfair".
"It is standard practice on social media for posts to occasionally get through," they said.
The "key responsibility" was "making sure that they are removed as soon admins become aware they violate online guidelines".
They added: "We are genuinely really sorry to those which rely on us, but we have to prioritise our own mental health and walk away from the page."
Police confirmed they were treating it as a "hate incident" and enquiries were ongoing.