French police investigating doping allegations against top cycling team Cofidis, which numbers Australian star Stuart O'Grady and world time-trial champion David Millar in its team, have detained two former riders and the team physio.

Stuart O'Grady, who has held the Tour de France yellow jersey, only joined the Cofidis team this year.

Police were also holding the wife and a pharmacist daughter of the physio as part of a judicial investigation into drug trafficking, the prosecutors' office at the Paris suburb of Nanterre said.

A stock of amphetamines, steroids, human growth hormone and the endurance-enhancer EPO (erythropoietin) were found at the home of the 2001 world track champion Robert Sassone when he was detained.

And medical files were seized at the team's headquarters.

Bogdan Madejak, the Polish physio of Cofidis suspected of supplying tour riders with banned substances, was arrested when he returned to France from Spain on Tuesday when his wife and both his daughters were detained. One of his daughters was later released.

Polish cyclist Marek Rutkiewicz, who also left Cofidis at the end of the year, was arrested at Charles de Gaulle airport on Monday when he returned from Warsaw.

Drugs officers acted after listening to Rutkiewicz's mobile phone calls from Poland.

"We're investigating a network dealing in EPO and steroids," a police source said.

Dr Jean-Jacques Menuet, the Cofidis team doctor, who also looks after the French athletics sprint team which includes European 200m champion Muriel Hurtis and former European 100m champion Christine Arron, has also been interviewed by the police.

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