Moscow - Russian swimming great Alexander Popov and Ukrainian pole vault legend Sergey Bubka, both IOC members, reacted furiously on Friday to claims they took bribes in exchange for supporting Rio de Janeiro as hosts for the 2016 Olympic Games.
"I didn't even vote for Rio de Janeiro," said Popov, one of three Russian members of the International Olympic Committee, in a statement released by RIA Novosti.
Bubka, who is also head of Ukraine's national Olympic committee, was also quick to deny the allegations, saying: "I completely reject all the false claims."
Brazilian media cited a former governor of Rio de Janeiro, Sergio Cabral, who is in prison on corruption charges, as saying at a court hearing that he helped to orchestrate a bribe to secure the city as host of the 2016 Summer Olympic Games.
He said the bribe, worth a combined $2 million, was organised with the help of Lamine Diack, the disgraced former head of athletics' world governing body the IAAF.
Diack resigned as an honorary IOC member in November 2015 and faces trial in France over corruption and money-laundering.
Among the people who allegedly received the funds, Cabral cited four-time Olympic gold medallist Popov as well as six-time world champion Bubka, who is the senior vice president of the IAAF.
He said the money was distributed by Brazilian businessman Arthur Soares. "I was assured that Sergei Bubka received the bribe... the Russian Alexander Popov as well."
Bubka said Diack "never contacted me about my vote".
"My lawyers will write to Mr Diack to ask him to explain the allegations of Mr Cabral who wrongly claims in his testimony that Mr Diack could secure my vote," Bubka said.
Popov on Friday said he "never participated in any negotiations on these topics or with the people mentioned in the media, I don't know them and never contacted them".
He added that he is "willing to give any information" on the matter to the IOC's ethics commission, and plans to file a defamation lawsuit in Switzerland.
The IOC said it would open an immediate investigation into the allegations, having contacted the IOC members mentioned in Cabral's testimony.
The IOC's chief ethics and compliance officer "has immediately followed up the allegations"," it said in a statement.
"The IOC is fully committed to address any issues, also those which happened before the far-reaching reforms of Olympic Agenda 2020.
"With these reforms the IOC has turned the page with regard to good governance and in particular the procedure of the election of host cities."