Image of terror: 78-year-old runner knocked over by second Boston Marathon blast

It is one of the shocking photographs that has already come to define yesterday’s Boston Marathon blasts: an elderly man in a bright orange shirt lies on the tarmac as three uniformed officers hover overhead, appearing not to know in what direction to run, whom to help, or how they can be of use, as the air fills with the residue of smoke, dulling the bright colours of the flags lining the streets.

The fallen man, Bill Iffrig, a 78-year-old running his third Boston Marathon, was near the finish line when the second of the two bomb blasts knocked him off his feet. He told The Herald of Everett he’d been a matter of metres from the explosion but was lucky to have only ended up with a scrape on his knee.

Following the explosion Mr Iffrig walked across the finishing line and hobbled another half-mile to his hotel. He was left “scared” and “dazed” by his shocking proximity to one of the two explosions which left three dead, including an 8-year-old boy, and 150 injured on America’s Patriot’s Day.

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His son, Mark Iffrig, of Seattle, told The Associated Press he was tracking his father's race progress online and had no idea what had happened until he went on Facebook and saw reports of the bombings. He quickly turned on the TV and called his dad.

"It's horrible. He said it was quite a concussive blast. [Dad] was a little dazed. Someone helped him up," Mark Iffrig said. "He was only about 10 feet (3 metres) from the finish line."

Mark Iffrig said the incident was unlikely to put his father, who has raced in a number of marathons, off running. "He's a hell of a runner," he said. "He's run a lot and he's fast."

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