What we know about the rape allegations levelled at UFC fighter Conor McGregor.

Ultimate Fighting Championship fighter Conor McGregor announced this week he was retiring from the sport he dominated.

The news came in the form of a tweet on Tuesday that gave no explanation as to why he was stepping away from the sport.

So it didn’t take some fans long to wonder if his retirement had anything to do with the rape allegations he’s been dogged by since December last year.

They don’t, says his New Jersey-based publicist Karen Kessler.

“This story has been circulating for some time and it is unclear why it is being reported now,” her statement read.

“The assumption that the Conor retirement announcement today is related to this rumour is absolutely false.”

Hey guys quick announcement, I’ve decided to retire from the sport formally known as “Mixed Martial Art” today.
I wish all my old colleagues well going forward in competition.
I now join my former partners on this venture, already in retirement.
Proper Pina Coladas on me fellas!

— Conor McGregor (@TheNotoriousMMA) March 26, 2019

But the allegations against Conor McGregor are more than just a “rumour” – they are the basis of a police investigation that saw the 30-year-old arrested, without charge, in January.

McGregor still hasn’t been charged with anything, and police in Ireland – where the assault allegedly occurred – are still investigating. But here’s what we know so far:

The sexual and physical assault allegedly took place at a hotel, The Beacon, in Dublin on 9 December 2018, or in the early hours of the next morning.

The woman’s name has not been printed, and her account of the events of that night come via police statements.

Police said the woman, a young mother, was raped and physically assaulted by a man. That man has been identified as McGregor by international media, but is referred only as a “sportsman” in Ireland because it is unlawful to report an accused rapist’s identity there until they are convicted.

The next day, a friend of the woman's told police and the woman was taken to a sexual assault treatment unit where she was treated and forensic samples were taken, The Irish Times reports.

The newspaper also reports that the woman was in a "highly traumatised state" and had "extensive bruising".

From there, police attempted to gather evidence from the hotel room, but as Irish media reported, investigators couldn't push forward until the woman made a formal statement, which she didn't do for weeks.

In January she decided to make a formal statement to police. Shortly after, on 17 January, McGregor was arrested at Dundrum police station, where he'd voluntarily gone to for questioning.

He was interviewed by police and gave a DNA sample, and then was released without charges being laid.

Police told the New York Times that they are continuing their investigation.

"Investigations are ongoing in this case and at this time a file continues to be prepared for the Director of Public Prosecutions," the police statement to the newspaper read.

The fighter, who has an almost-two-year-old son with his long-term girlfriend Dee Devlin, is no stranger to negative media attention or questioning by police.

In July he pleaded guilty to disorderly conduct after throwing a dolly into a bus last April resulting in two fighters being injured by shattered glass.

Then in January, he and Russian rival Khabib Nurmagomedov were suspended and fined for their roles in a fight outside of the cage that also involved their supporters in October.

And in March, McGregor was arrested for taking the phone of someone who tried to take a photo of him and smashing it in Miami.

McGregor hasn't publicly commented on the rape allegations. Nor has the UFC.