It’s been 40 years since the Jonestown Massacre in Guyana, where over 900 followers of the Reverend Jim Jones, founder of the Peoples Temple, died - by drinking cyanide-laced fruit punch, being injected with the poison, or by gunshot.

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Jackie Speier was a 28-year-old aide to U.S. Representative Leo Ryan at the time. She accompanied him on a visit to the settlement in November 1978, in the days leading up to the mass killing.

WATCH Jonestown Survivor Of U.S. State Department: ‘They Failed In Their Duty To Warn, Their Duty To Protect And The Duty To Investigate’

“Congressman Ryan went because many of his constituents had young adult children who had gotten involved in the church, she says,” adding, “They were concerned about mind control, they were concerned that their letters weren’t getting through, and so he wanted to find out firsthand.”

After meeting with Jones and speaking with his followers, Congressman Ryan, three members of the press and a would-be defector from the Peoples Temple were assassinated at an airfield during an attempt to help several members of the religious sect make their escape.

Speier, who is now a U.S. Representative, sustained five gunshot wounds during the attack and is one of a handful of people present who survived to tell the story.

Watch the video above to learn why the Congresswoman says she was “very concerned” about taking the trip to meet Jim Jones and what she says she did to prepare in case she failed to come home.

Congresswoman Jackie Speier is the author of “Undaunted: Surviving Jonestown, Summoning Courage, and Fighting Back.”

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‘I Still Carry Two Bullets,’ Says Jonestown Survivor 40 Years After She Was Shot