The spectre of drug abuse over the death of Olympic sprint champion Florence Griffith-Joyner emerged into the public arena yesterday, although a cautious International Olympic Committee (IOC) described her as a very great champion.

Experts on drug use in sport and a training partner believed Flo-Jo took drugs and spoke out on the dangers of banned substances in the wake of her death. But the IOC director general, Francois Carrard, pointed out that she never failed a drugs test.

Sadness and caution were the watchwords of the IOC. "We are very sad," said Carrard. "She was a very great champion who died prematurely."

When asked on the possibility of Flo-Jo having used drugs during her career, Carrard refused to speculate.

"We don't have an opinion because nothing is known about the matter. It is completely premature to give a decision," Carrard said.

And the IOC is unlikely to demand an inquiry into the death of the American. "At this stage we are not going to undertake proceedings," Carrard said. "We will see. I'm sure it's a matter which we will talk about again."

Initial autopsy results yesterday were inconclusive, according to police. "It could take a few days or a few weeks," said Lieutenant Hector Rivera of the Orange County Sheriff's Department in California.

Among the procedures carried out by the coroner was a toxicology test, which is done when the cause of death is unknown.

Tributes to Flo-Jo had poured out from all over the world, including from US president Bill Clinton, sprint legend Carl Lewis, high hurdler Greg Foster, and many others.

Griffith-Joyner was as famous for her lavish outfits, long fingernails and make-up as she was for her three Olympic titles at the 1988 Olympics in Seoul.

Police said an autopsy will be conducted, but she is believed to have died of a heart seizure similar to one she suffered in April of 1996 on a plane bound for St Louis.

Griffith-Joyner won the 100 and 200 metres at the Seoul Olympics and was on the 1988 gold medal 4x100 metres relay. She set a 100 metres world record of 10.49 seconds in the US Olympic trials and a 200 metres world record of 21.34 seconds at Seoul.

A former training partner of Flo-Jo is convinced the sprinter took a cocktail of drugs to make her the fastest woman on earth.

Lorna Boothe, a former Commonwealth silver medallist in the 110 metres hurdles, trained regularly with Griffith-Joyner in the build-up to the 1988 Seoul Olympics when the American's record-breaking performances helped her to three gold medals.

But Boothe, now the British athletics team manager, was amazed at the transformation of Griffith-Joyner and believes drugs may have played a role.

Boothe told the London Evening Standard: "I am astonished by the way Flo-Jo, a very good athlete in her own right, changed so incredibly from the slightly overweight, sluggish sprinter I was easily able to beat in training in California.

"She dramatically developed into sub-11 seconds form that Olympic summer. In 1987-88 I met a nurse who said she was working in a California hospital in what we called the Valley. "The nurse insisted that Flo-Jo was coming to the hospital regularly to be given a five-part cocktail of drugs, including steroids and testosterone.

"She was adamant about what she had seen. When I mentioned it to one of my coaches, who must have been looking out for some quick money, he contacted the local Press and I was told there was at least £25,000 in it for me.

"That was quite a lot of money to me at that time, but I definitely wasn't interested. I was just an athlete, training hard. I also knew that when it came to drugs of any kind round there you could easily get a hit man dealing with you and taking you out.

"Because of what I know intimately of the scene at that time in California I can only pray that she did not die from the longterm effect of using drugs in sport," she said.

"If she did then this would be a terrible warning to the young in athletics today."

German Werner Franke, an expert on drugs in sport, told public television station ZDF that he was certain Flo-Jo had died through drug abuse.

Franke believes information brought before the American Senate and comments from Griffith-Joyner's former training partner clearly prove that she had used drugs.

Franke said: "The first seizure of Griffith-Joyner in 1996 was already symptomatic of the abuse of anabolic drugs."

A French expert on drugs in sport, JeanPierre de Mondenard, told France Inter radio station: "For the specialists, there is no doubt. Her incredible physical transformation was not natural.

"Even if you trained eight, 10 or even 15 hours a day, it is humanly impossible to transform yourself in that way. By the drug use, she lost some of her cardio-vascular immunity. The process is known."