ZURICH, Aug 18: Former Olympic sprint champion Marion Jones has pulled out of Friday's Golden League meeting in Zurich and returned to the United States “for personal reasons”.

“We don't really know anything precise about her reasons,” media spokesman Christoph Schmid said.

“All we know is that she turned up at five o'clock in the morning and said she was leaving. Her manager told us it was for personal reasons.”

The 30-year-old triple Olympic gold medallist has been repeatedly dogged by doping accusations following her implication in the Balco laboratory scandal and her former involvement with coach Trevor Graham, although she has never failed a drugs test and has never been charged.

Jones is among a number of athletes who have been controversially banned from competing in the season's final Golden League meeting in Berlin, purely because of their ties to Graham, who is being investigated by the International Association of Athletics Federations (IAAF).

Organisers of the Zurich meeting refused to follow Berlin's example, arguing that concrete evidence would have to be brought against any athlete before a ban could be issued.

—Reuters