ATHLETICS/Balco scandal: Olympic champion Marion Jones was using drugs at the Sydney Games, according to her ex-husband, CJ Hunter, the San Francisco Chronicle has alleged.

The newspaper said former shot putter Hunter, who was himself banned for using steroids and was divorced from Jones in 2002, made the allegations to US federal investigators probing the Balco steroids scandal.

It said it had obtained investigators' memos containing Hunter's claims, which also said he sometimes personally injected Jones with banned performance-enhancing substances, which included the designer steroid THG, endurance-boosting EPO and human growth hormone.

Jones's lawyer, Joseph Burton, responded immediately with a statement branding Hunter as embittered and out for revenge.

"CJ Hunter has had an axe to grind ever since Marion Jones ended their marriage," the statement said.

"Fortunately, Hunter's efforts to exact his revenge by telling lies to the government are directly contradicted by the statements made to the government investigators of Marion Jones's former coach, who has supported everything Marion has said all along - that she never used performance-enhancing drugs."

Jones, who has dominated women's athletics in recent years, won the 100 and 200 metres at the 2000 Sydney Olympics, as well as a gold in the 4x400 metres relay, winning five medals in all.

Earlier this month she failed to qualify for the sprints at the US trials but is still set to compete in the long jump at the Athens Games next month.

She has adamantly denied using banned substances. The 28-year-old has also never failed a drugs test.

Burton's statement added: "CJ Hunter has made false statements to federal officials and we call upon federal authorities to investigate Hunter's conduct, as it is a crime to lie to federal investigators."

The Chronicle, whose article was mirrored in the San Jose Mercury, said the investigators' memos came from a 2½-hour interview with Hunter on June 8th in Raleigh, North Carolina, with a follow-up phone call a week later.

It said he alleged Jones was also using drugs before and after Sydney.

He reported seeing Jones inject herself with drugs at their residence in Australia.

According to his account, Jones got drugs from Victor Conte, owner of Balco (Bay Area Laboratory Co-Operative), and sometimes from her coach, Trevor Graham.

Conte faces charges of distributing drugs to athletes from several sports.

Balco's premises were raided last year after a previously undetectable steroid, THG (tetrahydrogestrinone), was linked to the company.

The Chronicle article was also contradicted by Joseph E Zeszotarski Jr, representing Jones's former coach.

"Trevor (Graham) has done nothing wrong, and the claims of wrongdoing attributed to him are completely false.

When all of the facts are presented it will be clear that Trevor has never been involved in any way in the distribution of any illicit substance."

The world 100-metre record holder, Tim Montgomery, Jones's partner, has been charged by the US Anti-Doping Agency (USADA) with a doping offence following the Balco scandal but has proclaimed his innocence and is taking his case to arbitration. He failed to make the US team and will miss the Olympics.

Travis Tygart, the USADA director of legal affairs, would not comment specifically on Hunter's allegations, but said: "USADA is extremely appreciative of those individuals who come forward with relevant information," adding that USADA followed up every lead it received.