American cyclist Floyd Landis and one of his former coaches went on trial in absentia on Thursday over allegations they spearheaded a plot to hack into an anti-doping laboratory's computers.

French court officials say Landis -- who was stripped of the 2006 Tour de France title for doping -- and former manager Arnie Baker never replied to a summons for the Paris trial.

They are among five defendants on trial following a sweeping French probe into alleged hacking based on claims from the Chatenay-Malabry anti-doping lab over intrusions into its computer system.

Baker is accused of having asked a consulting firm called Kargus Consultants to hack the lab's computers to try to discredit the tests showing Landis doped during the 2006 Tour.

Landis, in an email to The Associated Press, wrote that he had no information about the case except through the press, and was never summoned or contacted by the court -- despite its claims to the contrary. He said his lawyers in France were trying to find out why he's a defendant.

"However if we assume I'm accused of somehow conspiring to illegally acquire computer files from a lab by any means, which is all I've been able to conclude from the endless press releases, then the court is mistaken," he wrote. "I had nothing to do with any computer hacking."

Three other defendants were on hand: Thierry Lorho, a former agent with French spy agency DGSE; self-taught hacker Alain Quiros; and alleged intermediary and former paratrooper Jean-Francois Dominguez.

"What is this case? It's about three stooges who meet each other," Dominguez said in court. He and Lorho claimed they had no initial knowledge about the identity of the lab being hacked.

"That's a problem for me. For someone who has worked for so long in the intelligence business, it's odd that you wouldn't try to find out," presiding judge Isabelle Prevost-Desprez told Lorho.

The case centers on alleged use of a Trojan horse spy program in late 2006 to poke into the lab's computer system to extract information about Landis' file, months after he tested positive for doping.

The lab in Chatenay-Malabry, south of Paris, uncovered abnormally high testosterone levels in Landis' samples that were collected in the run-up to his 2006 Tour victory, and he was stripped of the title.

In January 2010, a French arrest warrant was issued for Baker and Landis so they could be questioned about the computer hacking, which dates to September 2006.

The trial continues Friday.