This posted less than an hour ago on l'Equipe's website:
By Philippe LE GARS et Damien RESSIOT
News to l'Equipe: Alexander Vinokourov, 33, leader of team Astana, tested positive for a homologous transfusion Saturday 21 July at the end of the individual Tour de France time trial whch he won at Albi. After analysis by the laboratory at Châtenay-Malabry, the blood taken at the finish showed the presence of two distinct populations of red cells in the A sample. In plain speech, this means that Vinokourov made use of a homologous transfusion shortly before the stage, utilizing blood from a compatible donor.
The Astana rider (about whom the Internation Cycling Union, in statements by its president, Pat McQuaid, had manifested its displeasure after he had admitted working with the sinister Dr. Michele Ferrari) underwent a new blood test in the late afternoon the day before yesterday, Monday, after his second victory in the 15th stage at Loudenvielle-LeLouron. This new sample is currently under analysis at Châtenay-Malabry, and could confirm the first positive result as early as tomorrow, since the two populations of red cells would still be observable.
Homologous transfusions, as distinct from autologous ones (in which the athlete's own blood is transfused) have been detectable since the Athens Olympic Games in 2004, by means of a method developed by the laboratory at Lausanne (LAD). American Tyler Hamilton was the first cyclist to test positive in this way, during the 2004 Vuelta.
PS. Following this revelation, team Astana, of which he was the leader, has decided to leave the Tour.
Update (7:25 pm Paris; 1:25 pm EDT.) Vinokourov has asked for a test of the B sample. Astana has said it withdrew its riders at the request of the Tour organizers. An emergency meeting of Tour de France team officials is currently underway.
(8:50 pm Paris; 2:50 pm EDT.) Twenty police are said to have carried out a search of the hotel in which team Astana was staying, and to have left with bags of evidence.