It was 30 years ago today that more than 900 people were led by the Reverend Jim Jones into a murder and suicide ritual of epic proportions.The killing began during California Congressman Leo Ryan's fact-finding mission to Guyana's jungle to investigate the remote commune built by Jones' California-based People's Temple.When Ryan and some church members tried to leave, a team of assassins opened fire. Ryan was fatally shot as he boarded his plane, making him the first congressman slain in the line of duty.Four others, including three newsmen, were also killed.Hundreds of people died at the compound later that day, most from cyanide poisoning.Some 400 unidentifiable or unclaimed bodies, most of them children, are now buried in a mass grave overlooking San Francisco Bay.