Cadena Ser radio said the Guardia Civil has several video recordings showing the athletes being injected by a sports physician.

El Pais and Marca dailies meanwhile reported that investigators seized four blood bags in the house of 77-year-old coach Manuel Pascua Piqueras, who was arrested Thursday (December 9) in the police operation.

The reports said the blood bags would indicate that athletes recently underwent a transfusion of their own blood.

Fourteen people were arrested Thursday as part of "Operacion Galgo" - which means Operation Greyhound in Spanish - including steeplechase world champion Marta Dominguez, 35, on suspicion of involvement with a doping ring supplying athletes with banned substances.

Dominquez, who was released along with five others after questioning, is expected to appear in court in her home city of Palencia at a later date.

The remaining suspects are expected to appear before a magistrate tomorrow.

The police operation was launched in April when investigators found evidence that a network of people might be facilitating illegal blood transfusions among sports professionals.

Police raided the homes of athletes, coaches and doctors in Madrid, Las Palmas, Alicante, Segovia and Palencia.

They seized large amounts of steroids, hormones and medication including erythropoietin (EPO), along with bags containing blood and documents about doping practices.

Those arrested include sports physician Eufemiano Fuentes, who in 2006 was at the centre of the biggest doping probe so far, Operation Puerto, which targeted cyclists, team officials and doctors over blood doping.


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