Despite failing to meet South African Olympic standards, Oscar Pistorius, the double-amputee runner who won a court battle to run against able-bodied athletes in international competitions, will compete in the 400 meters at the upcoming London Olympics.

Pistorius was selected for both the 400 and 4x400 relay by South Africa's Olympic committee in a surprise decision. He will become the first amputee to run at the Summer Olympics.

[Photos: Oscar Pistorius in action ]

"Today is really one of the happiest days of my life!" he wrote on Twitter. "Will be in London2012 for both the Olympic and Paralympic Games! Thank you to everyone that has made me the athlete I am! God, family and friends, my competitors and supporters! You have all had a hand!"

Pistorius had tried all year to get his second "A" cut in the 400, a time which would have given him an automatic berth to London under South African rules. When he failed to get the time on Friday, an individual Olympic berth seemed out of reach. But Pistorius still had the two fastest times of the year in the African country and that was enough to land him an individual spot. Tubby Reddy, Olympic committee chief executive, told the Associated Press that South African officials asked for permission to give Pistorius a bid despite his failure to qualify.

The South African 4x400 team will be defending a silver medal won at last year's world championships. Pistorius ran one of the legs in the heats and became the first amputee to win a medal at a major international competition.

His races will add interest to a London track program that's already overflowing with compelling storylines like the Usain Bolt-Yohan Blake rivalry.

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