Explosive documentary reveals new Waco standoff details

It's a secret that's haunted him for more than quarter of a century — but Larry Gilbreath has finally broken his silence.

The retired delivery driver gained a unique insight into the religious cult standoff in the quiet Texas town of Waco which left 76 people burned to death and shook the world in 1993.

In an explosive new documentary by CBS, the former Texas United Parcel Service worker reveals how he gained a unique insight into the brainwashed Branch Davidian followers' mountain hideout.

The group was suspected of weapons violations, causing a search and arrest warrant to be obtained by the Bureau of Alcohol, Tobacco, and Firearms (ATF) — resulting in a 51-day standoff.

The cult's compound was destroyed after government tanks rammed the building and agents fired tear gas. It culminated in a dramatic deadly explosion — killing scores of followers including nearly two dozen children.

In the new documentary, Gilbreath revealed how he unwittingly delivered large boxes of military grade guns and ammunition to the charismatic cult leader, David Koresh.

"I thought it was a little strange that religious people would be ordering guns," Gilbreath told 48 Hours.

"And I'd say probably 75 per cent of the time, when I would get there, David always came out. He signed for a lot of 'em. They just kept coming"

Over time the packages became bigger and heavier. To his horror, Gilbreath later learned he delivered ammunition for 223s, AK-47s, ART-15s, ammunition and even a grenade launcher to the cult.

In Texas, at the time, it was not illegal to receive large shipments of weapons.

In the documentary, he said it all changed when a box of hand grenades opened up before he could deliver them. Stunned and seeing his life "flash before his eyes", he confided in his wife Debra — who told the local sheriff.

The local police turned the matter over to the ATF and Gilbreath even began working with the ATF (Bureau of Alcohol, Tobacco, Firearms and Explosives) — joining in the undercover operation.

But, in a horrifying incident, Gilbreath revealed the moment Koresh told him he knew of the sting.

"Outta nowhere, David just looks at me, and says, 'Larry, I know they're watching us,'" Gilbreath said. "I went numb."

The 44-minute film also shows how Koresh failed in his ambitions to become a professional musician in California and instead turned to Bible bashing.

Journeying out to Texas, he locally took over a commune of the Branch Davidian church — calling himself the son of god — after a violent shootout with the church's leader at the time.

His prophecy was that a great apocalyptic battle with Babylon was coming and there would be destruction and fire and deaths.

In February, 1993, exiled cult members began claiming publicly that Koresh had physically abused children in the compound and committed statutory rape by taking underage brides.

Several former cult members have accused him of having sex with girls as young as 10 and impregnating them.

However, his message had spread as far as here in Australia and New Zealand. Followers jetsetted across the world to join the rock 'n' roll preacher in his cult compound.

New Zealander, Grace Adams, was one of those devoted followers who shared her story for the first time in the new film.

Aged 29, she and her younger sister Rebecca, 21, flew to join the church. But when the pair arrived at the hideout, it wasn't what they were expecting.

"David was on stage on a hospital bed and he was yelling and screaming and cussing," she told CBS. "There were children in the room.

"He had a boat paddle and he was hitting it on the stage. I'm thinking: 'Who is this man and what did we come to?'"

She describes how women cooked while men tended to the 77-acre property. But her experience quickly became sinister.

"If you wanted to go to heaven, you had to have sex with David," she said. "I was so terrified that I started to flip out I guess."

To get it over and done with, the 29-year-old knocked on Koresh's door and "offered herself" to him. But the fiery preacher was not pleased.

She described how he screamed at her in front of the other followers and locked her in a solitary cabin — because "only god" was supposed to choose his sexual partners.

The Kiwi was locked up for four months and fed from a bowl on the floor. Karesh came in one day and bashed her. But, when immigration came looking for her, the cult leader let her go.

She was treated in a Californian hospital before flying back to New Zealand.

It all changed for the cult when allegations surfaced that Koresh was stockpiling illegal weapons and thousands of rounds of ammunition, as well as operating a methamphetamine laboratory.

After reports of automatic gunfire coming from the compound, ATF issued warrants for Koresh and senior cult members on firearms charges.

On Sunday, February 28, 1993, ATF agents, their blood type written on their arms or neck, approached the site, hiding inside cattle trucks pulled by pick-up trucks.

Tipped off, Koresh and his cohorts began firing.

Four ATF agents were killed, 16 wounded and five Branch Davidians died before a ceasefire.

At around noon, three fires broke out in different parts of the compound, allegedly set alight by the Branch Davidians.

The fire spread trapping cult members, while others refused to leave, eventually perishing in the smoke and the blaze.

In all, only nine people escaped.

— with Candace Sutton