Ricky Hatton is to be investigated by police over allegations he snorted cocaine in a hotel room.
The 31-year-old boxer, who was admitted to a rehabilitation clinic on Monday, was secretly filmed allegedly snorting the class A drug while on a night out.
Greater Manchester Police said officers are aware of the story and plan to question him.
A spokesman said: "Police in Trafford are aware of the allegations made against Mr Hatton and are looking into the matter.
"Greater Manchester Police acknowledges that Mr Hatton has voluntarily entered rehabilitation and the force will respect his privacy.
"Once his rehabilitation has been completed, officers will be speaking to Mr Hatton about the allegations."
The two-weight world champion was out with friend Emma Bowe, an Irish national senior women's boxing champion, when he was caught on camera.
Hatton has battled with drink and severe depression for "several weeks", according to his spokesman Max Clifford, having not fought in the ring since May 2009.
His father Ray said the boxer signed himself into the clinic for an indefinite period.