US presidential candidate Robert F Kennedy was murdered in June 1968. It was less than five years after his older brother, President John F Kennedy, was also assassinated. Sirhan Sirhan was convicted of the crime, but many - including Kennedy's friend Paul Schrade - suspect another gunman was involved. Schrade was also shot that night. He's campaigning for the case to be reopened. [After speaking at The Ambassador Hotel in Los Angeles], Kennedy left the platform quickly. He went through a side door into a pantry next to the hotel kitchen. He came in alone. He didn't have his three bodyguards with him. A number of shots rang out and Kennedy fell to the ground, wounded in the head. And then I started shaking and I didn't know what was happening, I thought I'd been electrocuted or something, and I fell," [said Schrade]. "I'd been shot. I was in and out of consciousness. Most people in the pantry saw Sirhan firing at Kennedy. He was shot by somebody else, because at the same time, the second gunman fired behind Kennedy, four bullets at a very close range, at point blank range. The bullets taken from Kennedy were from a different gun. There were two different guns, two different bullets, two different shooters. The cover-up has lasted for years. Nobody knows who shot Robert Kennedy. They still say Sirhan is the lone gunman when he was not the lone gunman, based upon their own evidence. But we could never convince any district attorney or any police chief to reopen the case."