France could lose its team eventing qualifying spot for the 2016 Olympics after one of its horses failed a doping test at the World Equestrian Games.

Qalao des Mers, ridden by Maxime Livio of France, tested positive for a sedative in eventing on Aug. 29, the International Equestrian Federation said Friday. In another case, Tra Flama, ridden by Giliese de Villiers of South Africa, tested positive for an anti-inflammatory in endurance on Aug. 28.

"We carried out an intensive awareness campaign prior to the games and also offered pre-arrival testing to all participants," FEI secretary general Ingmar De Vos said in a statement. "So it is very disappointing that we have two positives for controlled medication substances at the games, especially when it is well known and well accepted that both these substances are not permitted in competition. Although these are controlled medication, not doping substances, we take this very seriously."

France qualified for the Olympics in Rio de Janeiro by finishing fourth in team eventing. But the positive test of Qalao des Mers could disqualify France.

Hearing dates have yet to be set.

Joanne Eccles of Britain won the women's vaulting contest in Friday's freestyle test. Eccles retained her world title by finishing ahead of Anna Cavallaro of Italy and Simone Jaiser of Switzerland.

Jasmin Lindner and Lukas Wacha gave Austria its first gold medal at the games by winning the pas de deux.

Lindner and Wacha, the 2013 European champions, dominated the freestyle test for the second straight day and were the only pair with a total above nine points.

German vaulters Pia Engelberty and Torben Jacobs took the silver medal, recovering from a disappointing fifth place in Thursday's freestyle. Joanne and Hannah Eccles of Britain were third.

The competition ends Sunday.

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