SAN FRANCISCO (KGO) -- This year marks the 40th anniversary of the Jonestown massacre, the largest murder-suicide in American history. It happened to American citizens living in a religious cult overseas, in the South American country of Guyana in 1978. Rep. Jackie Speier, D-Calif., was there in 1978 as a young aide to a congressman who was investigating suspicious activity at the compound, called Jonestown. But they were ambushed and shot while trying to leave. Speier says the lesson we need to learn, is be vigilant about religions that operate in secrecy.
VIDEO: Rep. Speier opens up about Jonestown massacre
"There are so many thoughts that run through your head when you're dying," she said. "And I was 28 years old. I had resigned myself to the fact that I was dying."
She survived, in spite of being shot five times by followers of the Reverend Jim Jones. He led a religious cult called The Peoples Temple. Speier was an aide to Congressman Leo Ryan. He was on a fact-finding mission to investigate complaints of sexual and physical abuse at the overseas compound in Guyana. He brought journalists to cover the story.
Speier said supporters of Jim Jones came and shot the Congressman.
"They shot Don Harris, the NBC reporter, the cameraman, the sound man, Greg Robinson, the Examiner photographer and me," she said.
Speier managed to drag her badly mangled body with one arm, behind the plane's wheel well. She and the others were on the airstrip for nearly 22 hours. Survivors were finally moved into a tent, still waiting for medical attention, which came much, much later.
She remembered this kindness at the time, "All I had was the goodness of some of the reporters and the producer from NBC who came and brought me rum, Guyanese rum, and I took swig of Guyanese rum to get through that night."
The ambush killed Ryan and four others, including three journalists.
Shortly after the attack, Jim Jones sent more than 900 of his followers at the Jonestown compound to their death. He ordered them to drink a cyanide-laced beverage. Speier says the children and infants were injected with cyanide.
Speier remains angry about major lapses from those days.
RELATED: Former Peoples Temple members describe horrors of Jonestown massacre, the day 918 Americans died
"What troubles me most as I look back at it, is that we had a State Department that failed us, we had local law enforcement that failed us, we had local government that failed us because there were so many telltale signs of illegal activity and that alone should have prompted scrutiny," she said.
The massacre in Guyana affected Speier's life in many ways. She's living with two bullets and shrapnel in her body. And she lives with Post Traumatic Stress Disorder, or PTSD.
Jennings: "Do you ever have moments of PTSD from those dark days?"
Speier: "I do whenever there's a 21 gun salute, or when fireworks go off or a particularly loud sound of some sort, car backfiring."
Speier says Jonestown taught her that we have to be suspicious of groups that operate in secrecy, while claiming the first amendment right of freedom of religion. They need to be reported if they commit crimes.
"I'm a Roman Catholic and I look at the Catholic Church and how they allowed these priests who were pedophiles to just be recirculated into another parish when they had an obligation to go to law enforcement and didn't," she said.
Speier has become fearless after surviving her near-death experience. She said: "Had Jonestown not happened, I don't know that I ever would have run for public office."
RELATED: 40 years after Jonestown massacre, ex-members describe Jim Jones as a 'real monster'
Her mentor, Congressman Ryan, would be so proud of Speier's journey. She points out, "That's the real power of being in elective office is you can shine a spotlight on issues that deserve attention. You can bring people together to find solutions to problems and it's really incredibly fulfilling."
You can hear Rep. Speier's full interview on Cheryl's Facebook page here.
And the congresswoman has a new book coming out next month, called "Undaunted."