Milwaukee - Athletic gear maker Nike and the bicycle maker that sponsors Lance Armstrong's racing team are cooperating with federal authorities investigating the seven-time Tour de France champion and others in cycling, spokespersons for both companies said on Friday.

Investigators requested documents from Trek Bicycle Corp. early in July and company officials complied fully, said Bill Mashek, a spokesperson for the Wisconsin-based company. He declined to say what those documents were. "One of the things investigators are seeking is for us not to comment," he said.

Nike spokesperson Derek Kent offered a similar comment.

"Yes, we have been contacted by the authorities regarding their investigation, and we are cooperating fully," Kent said. "At their request, we are not commenting further."

Armstrong has had a long relationship with Trek, which sponsors Armstrong's RadioShack racing team.

Trek is one of the world's largest bicycle manufacturers, making bikes for racing, commuting and mountain biking. Armstrong rode Trek bicycles in his Tour de France wins.

Federal investigators in Los Angeles are looking at drug use in professional cycling and have shown interest in Armstrong since former teammate Floyd Landis alleged this spring that Armstrong and others took performance-enhancing drugs. Landis was stripped of his 2006 Tour de France title for failing a drug test.

Armstrong strongly denies the accusations and his attorneys have complained that riders are unfairly being offered cozy deals if they provide investigators with claims that implicate Armstrong.

Mashek said Trek has no plans to drop Armstrong as an advertiser. "It's important to remember, these are just allegations," he said.