A girl’s piercing scream rang out as RFK fell in the early hours of June 5, 1968. When the young presidential candidate was shot by a Palestinian extremist, Sirhan Sirhan, Harry Benson was the only photographer present. During his Fleet Street days in the 1950s, Harry and his cronies would talk about how they’d handle a real, history-making scoop – what they’d do “if we were there”. As scoops go, Harry’s couldn’t have been bigger when it finally came along. Forty years later, they are testament to Kennedy’s fateful last days and shocking final moments.

He didn’t hear the gunfire, but when he heard the scream, Harry turned on his heel with his camera already halfway to his face. “This is what I came into the business for,” he thought, repeating it like a mantra in his head. “Don’t mess up now. Mess up tomorrow if you have to. This is history.”

Harry almost hadn’t turned up for Kennedy’s celebratory speech in LA that night. He’d had an invitation to dinner with friends, and had hurt his wrist playing tennis that morning at a private members’ club in Rodeo Drive (“Tennis is no sport for some scruff from Glasgow”). But something made him go.

Was it instinct? A sixth sense? No, says Harry; “I was enjoying my life over there. I had a nice lifestyle. And I didn’t want to have to go back to London, being sent out in the rain to photograph someone who fell off a train in Dulwich. I wanted to get better, to learn. I was seriously trying to break into American photography.”

Harry had arrived in the US in 1964 to photograph the Beatles in the year they conquered America. He has lived in Manhattan ever since. “It’s always felt like home,” he says. He has photographed every US president since Eisenhower. But the year he photographed RFK is particularly memorable: “I always think of 1968 as the year America had a nervous breakdown.”

When Harry entered the ballroom at the Ambassador hotel on the night of Kennedy’s assassination, he recalls Kennedy’s people were “making a big carry-on” in the run-up to the speech. RFK’s entourage was a trendy, close-knit group, famous for its parties. Known as the “honorary Kennedys”, many were friends of Bobby and his wife, Ethel. Their loyalties were often more socially motivated than ideological. “They were a very nice-looking bunch of young people,” Harry recalls. “They were jumping about, singing that embarrassing little song they had: ‘Sock it to ’em, Bobby, sock it to ’em, Bobby.’ ”

Shortly after midnight, Bobby appeared on the podium with Ethel on his right. He’d just won the California Democratic primary, a huge gain, and made a short speech thanking his supporters. He ended it with the words “On to Chicago” before stepping down, shaking hands with fans as he went. “People always wanted to touch him,” says Harry. The other photographers fought their way through the crush and left – they had what they’d come for. Harry stayed put.

Kennedy was supposed to attend a press conference next. He was ushered through a side door that led to a short cut through the hotel kitchen. Harry followed, realising the easiest way to avoid the crowds would be to follow RFK himself. He was three yards behind.

“A girl in one of those ‘Kennedy for President’ boaters screamed and I knew instantly what it was,” says Harry. “I turned and saw Bobby sink to the floor. The whole room seemed to be screaming. It was pandemonium. ”

Amid the panic, Harry clambered onto a work surface. “A single-mindedness takes over,” he says. From here, he photographed Ethel screaming at him, her palm spread, almost obscuring the shot. “That’s my favourite,” says Harry. “That’s it, right there: the crisis, the hysteria.” People were pushing and punching him: “Nobody says ‘Three cheers for the photographer’ in these situations.” Jesse Unruh, an assembly speaker for the Democratic party, thumped Harry from behind, knocking him to the floor for a few seconds. “While I was down there, I could see the blood pouring from Bobby’s head.” Looking around, Harry realised others were wounded too. “When the police came, the room calmed. I put the film in my sock so they couldn’t take it. I didn’t follow RFK to the hospital. I’d done enough.”

If the Kennedys found Harry intrusive, they didn’t bear a grudge. Since then, he has photographed them several times; in 1998 Ethel invited him to photograph the family together at her home on Bobby’s birthday. But Harry never quite became a friend. “I never liked the Kennedys,” he says. “I liked Bobby – there was a common touch about him; he was never patronising. But the rest thought the world owed them a living. I never go for dinner with the people I photograph. I don’t want Jack Nicholson to say to me over drinks, ‘Hey, Harry, you can’t use that shot of me in the bubble bath,’ because then I’ve got a problem with my new best friend. It’s not brain surgery, it’s simple. You’ve just got to be like an old dog that hasn’t been fed for a week.”

RFK: A Photographer’s Journal, by Harry Benson (Powerhouse Books, £25), is published on Friday.

It is available from BooksFirst for £22.50, including postage and packing. Tel: 0870 165 8585 Buy the book

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