By Amy Tennery

RIO DE JANEIRO (Reuters) - The suspension of canoe sprinter Serghei Tarnovschi, Moldova's first medal winner of the Rio Games, for failing a drugs test has disappointed fellow competitors who are alarmed by the frequency of doping cases in the sport.

Tarnovschi claimed bronze in the men's C-1 1000-metre sprint on Tuesday but was provisionally suspended from the Rio Olympics two days later for failing a pre-Games drug test, the International Canoe Federation (ICF) said.

ICF Secretary General Simon Toulson told Reuters the status of Tarnovschi's medal would be determined by an International Olympic Committee-led hearing.

Tarnovschi could not be immediately reached for comment. The Moldovan National Olympic Committee said it had requested official information about the case from the ICF and the World Anti-Doping Agency.

The news has cast a shadow over Tarnovschi's fellow athletes, who have spent years preparing for their Olympic contests.

Isaquias Queiroz dos Santos of Brazil, who took silver over Tarnovschi in the 1,000m C-1 sprint, told Reuters the news was a disappointment.

“I think that he [Tarnovschi] made a mistake, maybe due to being young," said Queiroz dos Santos, 22. "I’m very sad that this type of thing is happening in our sport." who has

Filip Dvorak, a canoeist for the Czech Republic who came in second in his C-2 1000m semi-final heat on Friday, said he supported a "zero tolerance" policy toward doping.

Dvorak also called the frequency of doping cases in his sport "really alarming."

In July, the ICF said it removed five Russian sprint canoeists from the Olympics. Last October, the Australian Sports Anti-Doping Authority gave a two-year ban to Olympic gold medal sprint kayaker Tate Smith for violations of a prohibited substance.

Doping cases overshadowed the run-up to Rio, with some 100 Russian competitors banned, and violations have continued to pile up.

Richard Pettit, ICF spokesman, said that the organization had a "robust zero-tolerance approach to doping violations."

"The fight to maintain clean sport is something that faces all International Federations and is an issue is taken exceptionally seriously," Pettit said.

The suspension prevented Tarnovschi and his brother Oleg from participating in Friday's men's canoe doubles 1000m heat at the Rodrigo de Freitas Lagoon.

Russia's Ilia Shtokalov, who finished fourth in Tuesday's race and narrowly missed out on a medal, could have a chance of bronze, depending on the outcome of Tarnovschi's hearing.

"He will have a lot of accusations going his way and I’m really sorry for the guy," said Shtokalov, 29. "But even if it’s confirmed, what can I say? He’s made his own choice here.”

(Additional reporting by Joshua Schneyer; Editing by Nina Chestney)