Billy Joe Saunders has apologised over a video described as "sickening" by police in which he appears to offer a woman drugs.
The WBO middleweight world champion was filmed in a car taunting the woman out of the window by seemingly offering "£150 of crack" in return for performing a sex act on another passenger in the vehicle and assaulting a passer-by.
The woman is seen striking a man in the footage before Saunders drives away. No drugs can be seen in the video and the 29-year-old has taken to Twitter to apologise.
"Apologise to everybody who's took offence," he wrote.
"Totally in the wrong, can't do anything but be sorry. 'Banter when (sic) wrong'. Apologies once again."
Police have started an investigation into the incident.
A Nottinghamshire Police spokesperson said: "[The force has been made] aware of a video circulating, where a woman is offered drugs in exchange for committing an act of violence, and potentially committing a sex act in public.
"Officers will be looking to identify and speak to all of those who feature in this sickening video, and a full investigation will be carried out into the number of offences that have been captured on film, including the offer to supply Class A drugs, aiding and abetting an assault, assault and public order offences.
"Incidents of this nature will not be tolerated in Nottinghamshire, and we would urge anyone who witnessed this incident, or who has any further information about those responsible to come forward."
The British Boxing Board of Control (BBBC) has charged Saunders with misconduct and a hearing will take place next week.
A widely released BBBC statement read: "The British Boxing Board of Control are aware of a video featuring WBO middleweight champion Billy Joe Saunders and have called Mr Saunders to appear before the Stewards of Board on a misconduct charge next week."
The unbeaten Saunders is scheduled to defend his title against Demetrius Andrade in Boston next month.
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