COLORADO SPRINGS, COLO. (AP) -- Though there are no Tour de France winners on the list, the U.S. Anti-Doping Agency has sanctioned five cyclists for doping in the past two months -- an unusually high number for a single sport, and one that is expected to keep growing over the next several weeks.

The recent surge has resulted from a combination of factors, including information provided by Joe Papp, a former midlevel rider who has been a key USADA informant since admitting in 2006 he cheated.

The cases create another problem for a sport that has been in turmoil, with Lance Armstrong under federal investigation and this year's Tour de France winner, Alberto Contador, among the latest to be accused of doping.

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