Shot-putter Inderjeet Singh Tuesday became the second Indian athlete to fail a drugs test in recent days, embroiling the nation's Olympic squad in a doping scandal before next month's Rio Games. The Asian champion claimed he was the victim of a conspiracy for criticizing sports authorities after his A sample taken during routine testing was found to contain a banned substance. "I am being targeted and it's a clear case of conspiracy against me. My sample has been tampered with," Singh, a gold medal winner at the Asian Athletics Championships last year, said in a statement. "Why would I take something which is not good for health?" "I have been framed because I am outspoken," the 28-year-old also told Indian TV stations. An Indian sports official said shotputter Singh tested positive for the banned steroid Androsterone during out-of-competition testing by the National Anti-Doping Agency (NADA) on June 22. "NADA has informed Inderjeet about the result. If he wants to test his B sample then it has to be done within seven days," said the official, who was speaking on condition of anonymity. The positive test comes after revelations that Rio-bound wrestler Narsingh Yadav, a Commonwealth Games gold medalist in the 74-kilogram freestyle category, also failed a drugs test. India has not yet decided the fate of either athlete. Yadav also cried foul, claiming his water and food supplements were contaminated with a banned steroid. The country is about to send its largest ever Olympic squad of more than 100 athletes in hopes of improving its poor medal count. "I was on the way to getting an Olympic medal for my country," a sobbing Singh told reporters Tuesday. "I deny all the allegations of doping that I am accused of." "I have been speaking out against the politics in sports in India and how badly athletes are treated and their poor training facilities, and this has riled many powerful people in the country. "Their intention is to shut me up." Navin Agarwal, the director-general of India's anti-doping agency NADA, denied that the samples could have been tampered, saying the samples are sealed in the presence of the athlete. Yadav said he feared his food supplements were spiked, but he did not reveal who was responsible for it. "I believe that there is foul play involved in this entire episode. Someone has sabotaged my food supplements and water intake," Yadav said Monday. Yadav, who had won a bronze at the 2015 World Championship to clinch a place in the Olympic team, failed successive dope tests when his samples tested positive for anabolic steroids. "This is a conspiracy against me. I am sure the truth will come out," Yadav said. Yadav said he was supported in his claim by the Indian Olympic Association and the Wrestling Federation of India. WFI President Brij Bhushan Sharan Singh said Yadav has made a formal complaint against officials of the Sports Authority of India and some others who he accused of acting against him, but did not reveal their identities. Yadav defeated Sushil Kumar, a two-time Olympic medalist, to get his place on India's team for Rio. Indian officials said if Yadav is disqualified, Kumar was unlikely to go instead because the cutoff for entries was July 18. The Rio Games are set to start on August 5 with controversy raging over the International Olympic Committee's decision not to impose a blanket ban to Russia, accused of state-sponsored doping. India has been rocked by previous drugs scandals and is ranked third on a global list of doping offenders compiled by the World Anti-Doping Agency, behind Russia and Italy. In 2011 six top Indian women runners tested positive for banned steroids.