t was supposed to have been a shared moment of human triumph.
But it took just seconds for the jubilation of the runners in the Boston Marathon – including more than 300 Britons – to turn to horror.
With the finishing straight at its most packed and the sidelines packed with spectators, the bomber couldn’t have chosen a better time to cause maximum carnage.
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Panic: People react as a bomb explodes near the finish line. 300 Britons were among the runners
Flashpoint: The moment of the explosion caught on camera by photographer Dan Lampariello
The blast that came at 2.50pm was just 100ft from the finish line. A blinding explosion of smoke and flame burst out into the street, shattering surrounding windows and ripping through the massed ranks of onlookers crowding against course barriers.
Bev Dowrick, a physiotherapist from Torpoint, Cornwall, had just finished the marathon and was walking to meet her husband in the family area when the bombs went off.
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‘I was about 300m away,’ she said. ‘You feel the explosion first of all, then you hear the bang and then the smoke. The police start running, the sirens start going.’
Any lingering doubts that it was a bomb attack were swept aside just 12 seconds later when another explosion, just a few hundred feet down the street, threw up another cloud of smoke and debris which, tragically, included the limbs blast victims.
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Fear: A Boston Marathon competitor and Boston police run from the area
The second explosion goes off (rear) as a runner was blown to the ground by the first explosion near the finish line
William Bowry, from Perth, Scotland, who works in Boston as a teacher, was looking for a friend who had finished the race when the ‘huge eruption’ shook the street.
‘When the second one went off, your mind leapt to the suspicion that it was a bomb,’ he said. ‘There was the noise and the fury of the explosion, and then you could quite palpably hear the screams and cries of panic.’
As the smoke subsided, and with an acrid smell hanging over the finish line, horrified onlookers realised the pavements were covered in blood, with body parts strewn across the street.
Nick Bailey 'thanks God' for a leg muscle injury on the Boston Marathon which meant he went slower than usual. He was a mile from the finish when the bombs went off
Boston fire chief Ron Harrington said it was the worst bloodshed he had seen in his 28-year career.
‘Bodies and body parts. Blood all over. A little boy lying in the street. A young woman in her twenties.
'Both dead. It was mayhem,’ he said. ‘I saw two people with arms hanging loose, and one without a leg. A shoe with flesh still in it.’
Witnesses compared the scene to the carnage of a bomb-blasted Baghdad.
For many, the shock swiftly gave way to panic as they sought out their loved ones.
Peregrine Hood, a 38-year-old foreign exchange dealer from London and friend of Prince William, was taking part in the race. He could only watch as his British girlfriend, Serena Nikkhah, ran to safety as a bomb went off just yards away.
‘She literally ran for her life,’ he said.
Mr Hood, son of Viscount Bridport, said it took him a nerve-racking half hour to get an email reply from Miss Nikkhah, a 29-year-old fashion editor at Vogue, indicating she was safe.
As many fled the scene, police, ambulance crews and race volunteers courageously ran in the opposite direction down the marathon route, pulling down metal barriers and the flags of competing nations as they tried to reach the injured.
Videos show runners ripping off shorts and shirts and using them as tourniquets on the legs of the wounded.
The confusion spread further back into the race as competitors learnt, often from other panicked runners heading back towards them or from police and race volunteers stepping out into their path, that something had gone badly wrong.
Boston Marathon bombing caught on video WARNING GRAPHIC CONTENT
Panic: Emergency responders comfort a woman on a stretcher who was injured in a bomb blast
Carnage: Police react in the aftermath of the double explosion
At the 25 mile-mark, a police officer broke the news telling runners: ‘The race is over, folks. There is no finish line.’
With classic British understatement, Nick Bailey, a teacher from Chichester, described how he had pulled a muscle towards the end of the marathon and had to slow down.
‘Sometimes it’s good to be a little slow,’ the 56-year-old said.
Fear and grief: Two women run in the vicinity after the blasts and a woman kneels and prays at the scene of the first explosion on Boylston Street
Eamon Loughran, a runner from Northern Ireland, said he prayed for three hours as he waited to be reunited with his wife, Angela, who he had arranged to meet by the finishing line.
Thinking the worst, he returned to his hotel and paced back and forth in their room. They both burst into tears when she walked through the door, he said.
‘She was worried about me and I was so relieved, thankful to God.’
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