(CNN) -- U.S. Open tennis champion Andy Murray has condemned the handling of the Operation Puerto doping trial by the Spanish authorities, accusing them of the "biggest cover up in sports history."
A criminal trial in Spain concluded Tuesday with sports doctor Eufemiano Fuentes given a one-year jail term for supplying cyclists with blood transfusions to boost their performance.
But the judge hearing the case, Julia Patricia Santamaria, ordered that over 200 bags of blood and plasma seized from Fuentes, be destroyed, pending any appeals.
Murray, an outspoken critic of doping, used his Twitter blog to express his frustration.
"Puerto case is beyond a joke... biggest cover up in sports history?," he tweeted
"Why would court order blood bags to be destroyed? #coverup."
During his trial, Fuentes gave evidence that he had clients from other sports, including tennis, football, boxing and athletics, but did not identify them.
At the time of his arrest and the raids on his premises in 2006, doping was not a criminal offense in Spain, but he was found guilty of endangering public health.
He was also barred from practicing as a sports doctor for four years, but under the Spanish legal system his jail term will be suspended.
The World Anti Doping Agency (WADA) also expressed its disagreement with the court decision Wednesday.
"The decision to order the destruction of all the blood bags is particularly disappointing and unsatisfactory for WADA, and the whole anti-doping community," it said in a statement.
"Access to this evidence motivated WADA's involvement in this case. This would ensure appropriate sports sanction processes against the cheats who used Dr Fuentes' services."
WADA said it was reviewing its next course of action in conjunction with the Spanish National Anti-Doping Organization (AEA).
The deadline to appeal the court decision is May 17
The International Olympic Committee signaled its frustration with the court ruling Wednesday.
"It's unfortunate that the evidence used in this proceeding is not now being made available to anti-doping organizations to further the fight against doping," it said in a statement.
British No.1 Murray went public in February with his demand for more blood testing in tennis, saying it needed to do everything it could "to ensure that everyone competing at the highest level and below is clean."
He was joined by fellow grand slam winners Roger Federer, Novak Djokovic and Rafael Nadal in demanding stricter tests and in March the International Tennis Federation announced it would be introducing a Biological Passport program - a more stringent control against doping.