Tyson Fury has posted a cryptic tweet amid reports of a positive test for cocaine.

So far, the world heavyweight champion's camp has refused to comment on the claims from ESPN, but the fighter shared an image on Twitter from the film Scarface, which shows the main character Tony Montana sat with a pile of cocaine on a table in front of him.

Fury has imposed his face onto the picture, with the hashtag #tysonmontana which does little to clear up the confusion surrounding the reports.

US-based sports broadcaster ESPN reported Fury tested positive after giving a urine sample on September 22nd.

It said Fury was tested in Lancaster, England by the Las Vegas-based Voluntary Anti-Doping Association (VADA), as part of the routine agreed by Fury and Wladimir Klitschko before their now-cancelled fight.

Cocaine, while being an illegal Class A drug, is not banned out of competition.

Sources have said the VADA test was taken on an in-competition basis.

A spokesman for Fury’s promoter Hennessy Sports declined to discuss the ESPN claims.

Fury had been due to fight Klitschko in Manchester on October 29th, defending the WBA and WBO heavyweight belts he took off the Ukrainian last November, but that clash was postponed on September 23rd.

One attempt at a rematch — set for July 9th — had already been shelved because of an ankle injury sustained by Fury.

A source close to the postponed fight said he had been informed “traces” of cocaine were found in Fury’s system. The 28-year-old fighter’s camp would not confirm that.

VADA, which states on its website it specialises in testing competitors from boxing and mixed martial arts, said it does not release results of samples unless at an athlete’s request when contacted regarding Fury.

WBO president Paco Valcarcel said his organisation was waiting to see the paperwork involved in the tests before reaching any judgement.

He said: “We have to wait for the British board to notify us of the information they have got regarding the doping tests.”

Asked whether Fury risked losing his WBO belt, Valcarcel added: “We don’t want to go any further until we receive the medical certification and the results.”

ESPN reported details of a letter from VADA president Dr Margaret Goodman that it said was sent to both fighters plus the British Boxing Board of Control and the United States’ Association of Boxing Commissions on Thursday.

It stated that the letter read: “This letter is to advise you that the ‘A’ sample urine specimen number 4006253 collected from Tyson Fury on September 22th, 2016 in Lancaster, England through his participation in the Voluntary Anti-Doping Association (VADA) program has been analysed for anabolic agents, diuretics, beta-2 agonists, stimulants and drugs of abuse.

“The results of the analysis are as follows: Adverse. Urine specimen contains benzoylecgonine. Mr Fury has the right to promptly request analysis of the ‘B’ sample at his expense.”

Benzoylecgonine is a metabolite of cocaine.

It remains to be seen whether Fury loses his belts, having failed to make a title defence this year.

After the cancellation of the July 9th fight, it emerged that UK-Anti Doping (UKAD) had charged the champion over a urine sample taken in February 2015, and his cousin Hughie with a doping offence. They deny wrongdoing.

It was alleged the sample — taken nine months before Tyson Fury’s defeat of Klitschko — contained traces of the banned substance nandrolone. Fury was provisionally suspended, but that ban has since been lifted, and his legal team said they would be suing UKAD over the allegations.

His hearing will be held in November.