Five Vietnamese athletes failed doping tests and will be stripped of their nine medals, including five golds, won at the 31st Southeast Asian (SEA) Games held in Vietnam in May last year, the Southeast Asian Sports Council announced on Thursday. Following the forfeiture of the gold medals, the Vietnamese athletics team will see their gold medal tally down to 17 from 22. The five Vietnamese athletes explained that they had used a type of supplement without knowing it contained banned substances. Five Vietnamese athletes failed doping tests and will be stripped of their nine medals, including five golds, won at the 31st Southeast Asian (SEA) Games held in Vietnam in May last year, the Southeast Asian Sports Council announced on Thursday. The five Vietnamese athletes explained that they had used a type of supplement without knowing it contained banned substances.