Today marks 50 years since the assassination of Robert F Kennedy at the Ambassador Hotel in Los Angeles.

The aspiring Democratic presidential candidate, 42, who had just defeated Eugene McCarthy to win the California presidential primaries, was attempting to leave a campaign rally in the venue's ballroom by a kitchen corridor when he was shot shortly after midnight on 5 June 1968.

His assailant was Sirhan Sirhan, 24, a Palestinian holding Jordanian citizenship, who burst through the crowd of well-wishers to fire a .22 calibre Iver Johnson Cadet revolver at Kennedy.

The candidate, mobbed by jubilant supporters overjoyed by his victory, was shaking hands with hotel dishwasher Juan Romero, 17, at the time, and fell to the ground immediately when Sirhan started shooting.

Five others were injured in the melee that ensued: journalists William Weisel and Ira Goldstein, United Auto Workers union representative Paul Schrade, Democratic activist Elizabeth Evans and campaign volunteer Irwin Stroll.

​Sirhan was punched twice and disarmed by Kennedy's bodyguard, former FBI agent William Barry, and restrained by writer George Plimpton and others.

As the injured candidate lay on the ground, Barry laid his jacket over him while Romero cradled his head, clutching a rosary.

"Is everybody OK?" Kennedy asked.

"Yes, everybody's OK, " Romero replied. "Everything's going to be OK."

The moment was captured by photographers Bill Eppridge and Bill Yaro of Life magazine and The Los Angeles Times respectively, their pictures among the most famous press photographs of the 20th century.

The sea of shocked supporters parted to allow the candidate's wife Ethel Kennedy through (then three months pregnant) to comfort her dying husband. Journalist Peter Hamill reported noticing "a sweet accepting smile" on Kennedy's face.

"Don't lift me", Bobby said, as paramedics attempted to move him onto a stretcher, an expression of agony that would prove to be his final words in this life.

Taken first to the nearby Central Receiving Hospital before being transferred to the Hospital of the Good Samaritan for emergency surgery, Kennedy was operated on for almost four hours to no avail.

Robert F Kennedy was pronounced dead at 2am on 6 June, almost 26 hours after the attack had taken place, killed by three bullet wounds to the head, neck and chest. History had repeated itself in the cruellest fashion less than five years on from the death of his brother John in Dallas, Texas.

Bobby's body was taken to St Patrick's Cathedral in Manhattan, New York City, where it lay for public viewing until his funeral on 8 June.

The last surviving Kennedy brother, Massachusetts Senator Ted Kennedy, voice quavering, gave a moving eulogy, speaking in simple and clear language:

"My brother need not be idealised, or enlarged in death beyond what he was in life; to be remembered simply as a good and decent man, who saw wrong and tried to right it, saw suffering and tried to heal it, saw war and tried to stop it. Those of us who loved him and who take him to his rest today, pray that what he was to us and what he wished for others will someday come to pass for all the world.

"As he said many times, in many parts of this nation, to those he touched and who sought to touch him: 'Some men see things as they are and say why. I dream things that never were and say why not.'"

Kennedy's coffin was subsequently conveyed to Washington, DC, by rail – thousands of mourners lining the tracks – and buried at Arlington National Cemetery, in close proximity to John's grave.

Vice president Hubert Humphrey secured the Democratic presidential nomination that might have been Kennedy's, only to lose the 1968 election to Republican Richard Nixon.

For his part, Sirhan – still alive today and serving out a life sentence at the Richard J Donovan Correctional Facility in San Diego – was an unstable man who had become fixated on Bobby, writing in his journal of his "determination to eliminate RFK" over his support for Israel.

The tragedy of Bobby Kennedy's murder was nothing less than the death of hope.

Following the assassinations of his sibling – the first sitting president to be killed in office since William McKinley in 1901 – and of civil rights leader Dr Martin Luther King Jr, about whom Bobby had spoken so movingly earlier that spring in Indianapolis, the Sixties dream of a better tomorrow seemed lost.

"My thanks to all of you; and now it's on to Chicago, and let's win there!" he told the crowd in California on the night he was shot, his last public address.

Bobby may not have been the shining prince of Camelot he was made out to be – some felt he remained compromised by his early career as an aide to Communist witchfinder-general Joseph McCarthy – but many sincerely believed in him as an idealist who felt that peace was achievable and worth fighting for.

The young New York senator's clothes were torn at on the campaign trail by excited fans, his motorcades passing through town always whipping up a feverish atmosphere akin to Beatlemania, a source of nagging concern to his security detail who feared they could not control the crowd when Bobby waded into their midst to shake hands.

Kennedy's work in support of California's immigrant farm labourers from Mexico, the coal miners of Appalachia and the inner city poor was part of a wider sympathy for minorities he felt deeply as a devout Catholic.

He hoped to withdraw America from its unwinnable war in Vietnam and believed that tackling racial prejudice and job creation were the priorities the country needed to focus on to restore present stability and future prosperity in a moment of national conflict and rioting.

In truth – and despite the superb campaigns he ran for senate and the presidency on behalf of John – the handsome young man who stood for reconciliation and law and order may have struggled to win the White House.

A Day That Shook The World: John F. Kennedy assassinated Show all 8 1 /8 A Day That Shook The World: John F. Kennedy assassinated A Day That Shook The World: John F. Kennedy assassinated President John F. Kennedy (1917 - 1963) and his wife Jacqueline Kennedy ride with secret agents in an open car motorcade shortly before the president was assassinated in Dallas, Texas, November 22, 1963. Getty Images A Day That Shook The World: John F. Kennedy assassinated Cliff Michelmore pointing to the path of gun shots which killed President John F Kennedy, on a model reconstruction of the Dealey Plaza, Dallas, in the USA. Getty Images A Day That Shook The World: John F. Kennedy assassinated A man holding the rifle used by Lee Harvey Oswald in his assassination of the American President John F Kennedy. Getty Images A Day That Shook The World: John F. Kennedy assassinated circa 1965: The Texas School Book Depository at Dallas, Texas, from which US president John F Kennedy is thought to have been shot. Getty Images A Day That Shook The World: John F. Kennedy assassinated 23rd November 1963: A woman buys a newspaper from a street vendor for the latest headlines concerning the assassination of John F Kennedy. Getty Images A Day That Shook The World: John F. Kennedy assassinated The family and friends of the assassinated American President John F Kennedy (1917 - 1963) mourning his death. Getty Images A Day That Shook The World: John F. Kennedy assassinated Members of the Kennedy family at the funeral of assassinated president John F. Kennedy at Washington DC. From left: Senator Edward Kennedy, Caroline Kennedy, (aged 6), Jackie Kennedy (1929 - 1994), Attorney General Robert Kennedy and John Kennedy (1960 - 1999) (aged 3). Getty Images A Day That Shook The World: John F. Kennedy assassinated 22nd November 1963: US statesman John F Kennedy, 35th president of the US, and his wife Jackie Kennedy travelling in the presidential motorcade at Dallas, before his assassination. Getty Images

He had alienated President Lyndon Johnson with stinging criticism, upset the unions as attorney-general with his investigation into organised graft and alarmed corporate America with his ever-more leftist stance.

As a wealthy Bostonian outsider, the power of his appeal to unite America's minorities under a centrist coalition of the downtrodden has been doubted while the anti-war generation seemed likely to prefer his professorial Minnesota rival Eugene McCarthy as party candidate for president, the latter much stronger in denouncing American involvement in Vietnam.

Nevertheless, the myth of Bobby Kennedy endures. He stands for all unrealised possibilities, every promise cruelly snatched away and denied the chance to grow to fruition.