The former rector of the University of Siena, and a former mayor of the Tuscan city, has accused some of the trainers of the horses that compete in the traditional "Palio" race in Siena's Piazza del Campo of giving the horses heavy doses of amphetamines to stimulate them in the brutal no-holds-barred race round the piazza, writes Paul Bompard in Rome.
Mauro Barni, 70, an expert in forensic medicine, made his accusations following the deaths of two horses during the August 16 Palio. Both horses crashed into the outside wall, broke legs and had to be put down.
This produced an immediate outcry from animal defence groups that for years have charged the Palio, which has been run twice a year since 1546, with being needlessly cruel to the horses.
Professor Barni told how when he was mayor one of the Palio horses suddenly died in its stable.
"I quietly sent the dead horse to be examined at the Institute of Forensic Medicine in the University of Pisa. The horse turned out to be intoxicated with amphetamines, which had produced damage to the liver and death."
Barni says that "all you have to do is look at some of the horses to understand that they are drugged".
He said: "The horses seem to be in the grip of euphoria, insensitive to danger. They crash into stone columns and wound themselves horribly. Years ago the Palio race was almost always a match between the three or four favourites. Nowadays you get incredibly unexpected performances from total outsiders.
"Anybody who lives in Siena and has eyes to see with must know that drugs are used. Six or seven years ago I proposed a system of anti-drug tests, but I was showered with insults by my fellow citizens."
Judges in Siena have announced they are investigating the death of the two horses last month and have ordered autopsies to be performed.