Di Luca also won the prestigious Liege-Bastogne-Liege race in 2007

Giro d'Italia winner Danilo Di Luca has been cleared of doping by an Italian Olympic Committee (Coni) commission because of insufficient evidence.

Coni had wanted Di Luca banned for two years for showing abnormally low hormone levels during last May's race.

But a spokesman said there was "not a sufficient degree of probability" to rule against the 32-year-old.

An initial hearing took place on 1 April after nearly a year of wrangling over complex scientific data.

At that hearing, the commission decided it could not make a ruling and asked three independent experts to consider the case.

Their report to the commission on Wednesday said there was still no clear explanation as to why Di Luca's hormone levels were so low.

At the first hearing, the defence argued that the levels were caused by the rider drinking a lot of water before being tested.

It claimed tests had been carried out on volunteers who exhibited similar hormone levels having drunk water.

Coni's anti-doping prosecutor maintained that the reading was caused by the use of an intravenous drip, possibly containing plasma.

Di Luca was handed a three-month ban by Coni last October because of his ties to a doctor who served a five-year suspension for allegedly supplying doping products.

The rider protested his innocence, describing the ban as "an injustice".