SANTIAGO (AFP) — Chile's top cyclist Marco Arriagada announced he has tested positive for banned substances but has pledged to prove his innocence. Arriagada tested positive during the Tour of Chile, a race he has won three times, in February. According to press reports the 35-year-old's sample tested positive for anabolic steroids. ""The Federation told me the news and now I have to discuss it with my lawyers,"" Arriagada told the website of Chilean daily El Mercurio from the Dominican Republic. He will be returning immediately ""to undergo the necessary tests and prove my innocence,"" he added. Arriagada won three of the 10 stages on the last edition of the Tour of Chile and is a four-time national time trial champion.