* South Africa's "Blade Runner" to appear in court

* Charged with murdering his girlfriend

* Nation stunned by fate of sporting hero

By Ed Cropley

JOHANNESBURG - South African 'Blade Runner' Oscar Pistorius, a double amputee who became one of the biggest names in world athletics, is due to appear in court on Friday on charges of murdering his girlfriend.

South African "Blade Runner" Oscar Pistorius (R) is escorted by police at a Pretoria police station February 14, 2013. Pistorius, a double amputee who became one of the biggest names in world athletics, was charged on Thursday with shooting dead his girlfriend, model Reeva Steenkamp, at his upscale home in Pretoria. [Photo/Agencies]

The arrest of the 26-year-old Olympic and Paralympic track star stunned a nation that holds him up as hero who triumphed over adversity to compete with able-bodied athletes at the highest levels of sport.

His girlfriend, model Reeva Steenkamp, was found shot dead in his plush Pretoria home in the early hours of Thursday, police said, announcing that they had opened a murder investigation.

Initial reports of the shooting suggested Pistorius may have mistaken Steenkamp for an intruder.

The evening edition of Johannesburg's Star newspaper plastered the case across its front page, with a banner headline: "Oscar arrested: Girlfriend killed".

A 9 mm pistol was recovered from the scene, and police said there had been previous incidents of "a domestic nature" at the residence, which sits in the middle of a heavily guarded gated complex in the northern outskirts of the South African capital.

Pistorius had initially been expected to appear in court on Thursday but the hearing was postponed to Friday, National Prosecuting Authority officials said. The court is due to open at 0700 GMT but it is not known when Pistorius will appear.

He is being held overnight at Pretoria's Boschkop police station after undergoing medical and forensic examinations, police said. Police have said they will oppose bail.

"He is doing well but very emotional" his lawyer, Kenny Oldwage, told SABC TV, but gave no further comment.

South Africa's M-Net cable TV channel immediately pulled adverts featuring Pistorius off air but most of his sponsors, including sports apparel group Nike, said they would not make any decisions until the police investigation is completed.

Pistorius' endorsements and sponsorships, which also include British telecoms firm BT, sunglasses maker Oakley and French designer Thierry Mugler, are thought to be worth as much as $2 million a year.

Pistorius, who was born without a fibula in both legs, was the first double amputee to run in the Olympics and reached the 400-metres semi-finals in London 2012.

In last year's Paralympics he suffered his first loss over 200 metres in nine years. After the race he questioned the legitimacy of Brazilian winner Alan Oliveira's prosthetic blades, but was quick to express regret for the comments.

South Africa has some of the world's highest rates of violent crime, and many home owners have weapons to defend themselves against intruders, although Pistorius' complex is surrounded by a three-metre high wall and electric fence.