Oscar Pistorius stunningly lost his 200m Paralympic crown tonight - then caused major controversy by questioning the length of the blades of the man who beat him.

The South African is known as the Blade Runner, but after he was beaten in the T44 200m by Brazil's Alan Fonteles Oliveira he questioned the International Paralympic Committee's regulations surrounding the prosthetics.

Oliveira chased down Pistorius on the straight to win in 21.45 seconds, 0.07secs ahead of his rival.

But Pistorius let rip afterwards, criticising the IPC's rules and even questioning whether they were followed.

He told Channel 4: "You saw how far he came back. We aren't racing a fair race. I gave it my best.

"The IPC have their regulations. The regulations [allow] that athletes can make themselves unbelievably high.

"We've tried to address the issue with them in the weeks up to this and it's just been falling on deaf ears.

"You saw [American athlete] Blake Leeper yesterday when the guy came down literally overnight, made his blades longer. His knee height is like four inches higher than it should be.

"The guys are just running ridiculous times and they're able to do so.

"I think Alan's a great athlete but...I run just over 10 metres per second, I don't know how you can come back, watching the replay, from eight metres behind on the 100 to win.

"It's absolutely ridiculous."

Standard procedure is for prosthetic blades to be measured before competition, but Pistorius said: "The guys rarely do the measuring in the call room."

The IPC responded by making it clear their regulations were followed.

Their statement read: "There is a rule in place regarding the length of the blades which is determined by a formula based on the height and dynamics of the athlete.

"All athletes were measured today prior to competition by a classifier and all were approved for competition."

Oliveira's time was outside the world record Pistorius set in qualifying for the final yesterday. And he shrugged off any suggestion he was getting an unfair advantage.

Speaking through an interpreter, Oliveira told Channel 4: "The length of my blades is all right, I went through all the procedures with the referees. Once I come inside the track it's because it's all been cleared up and I believe Pistorius also knows that."

Asked if he had changed the length of his blades between the semi and the final, Oliveira replied: "No. Since the first time I put them on they've been following the IPC rules and I've been using them already for a whole month, just the same blades."

Despite the controversy, the Brazilian was soaking in the moment.

"I am very happy," he said. "This day I am writing my story on the Paralympic world. Alan Fonteles: Paralympic champion."