Lurdes Pires rolled herself up in a sleeping mat to avoid detection in Timor-Leste's villages, where she was helping people understand the voting process for an independence referendum.

Ms Pires smuggled herself from Darwin into Timor-Leste for this task in 1999, without her mother's knowledge, and left one day after the August 30 vote.

Vaughan Williams put up hundreds of posters around Darwin throughout the 1990s. ( Supplied: Vaughan Williams )

"If I was scared or if people had come in and searched the area and I didn't have time to run, the people would roll me in this mat and just pretend that it was like a mattress or something like that," she said.

Ms Pires fled Indonesian occupied Timor-Leste with her parents in 1975 and arrived in Darwin less than a year after the city had been flattened by Cyclone Tracy.

"It was crazy to stay in Darwin, however we stayed in Darwin because we wanted to be close to home and we wanted to help the country become independent," she said.

"Working together with activists and more people knowing about our struggle, Darwin became the centre of information dissemination.

"Everything happened here in Darwin."

Robert Wesley-Smith was one of those activists, and his home in the city's rural area now resembles a Timor-Leste history museum.

Old photos, posters, meticulously filed newspaper cuttings and press releases reveal a lifelong dedication to the country and its fight for independence.

Mr Wesley-Smith was a founding member of Australians for a Free East Timor, a Darwin community response to the massacre of independence supporters at Dili's Santa Cruz cemetery in 1991.

Darwin resident Lurdes Pires fled from Timor-Leste with her parents in 1975 after Indonesian occupation. ( ABC News: Felicity James )

He worked closely with Timorese-Australian student Cesarina Rocha.

"We did our actions in a timed sort of way [so] that information could then spread around the rest of Australia and the world," Mr Wesley-Smith said.

"We'd do a lot of our rallies in the morning and down south they'd do them in the evening.

"Timor's the closest country overseas to us here; we all knew what was happening."

After news of the 1991 shootings reached Australia, Mr Wesley-Smith instructed hundreds of protesters to lie side-by-side in one of Darwin's main streets to represent a then-disputed death toll.

Jessie Watson, Sally-Anne Watson, and Rob Wesley-Smith in front of the torture photos smuggled out of Timor-Leste and put on display in Darwin. ( Supplied: Vaughan Williams )

"It was pretty dramatic, and the cops were there supporting us," Mr Wesley-Smith said.

"They marched to the Indonesian consulate in Stuart Park and stayed on the footpath until December 7, the anniversary of the invasion."

'I know what happened to my brother'

Twenty years after Timor-Leste voted overwhelmingly for independence from Indonesian occupation, other former members of the activist group have also reflected on their contribution.

Their actions captured public and police attention but, according to Vaughan Williams, some police were also sympathetic to their cause.

"We would go out and do 200 posters in a night," he said.

"It was quite funny when we were doing poster runs, we would have police come up to us and say, 'which side of town you going to be on tonight?'"

Police would then stick to the other side of town, according to Mr Williams.

After news of Dili's 1991 Santa Cruz massacre reached Darwin, hundreds protested by lying in the streets. ( littledarwin blog )

Along with prolific poster runs, protests and arrests, the group smuggled photos taken as trophy shots out of occupied Timor-Leste to put on public display.

The photographs showed the bodies of adults and children who had been tortured, raped and killed, and group member Cindy Watson exhibited them in her shop.

"It was a major tool of people actually seeing, not just a snippet in the newspaper, not just an interview of someone relaying what had happened," she said.

"It was hard, cold, really brutal proof of what was happening."

One man discovered his brother had been killed because of the exhibition, which put to rest claims the photos were fake.

"A Timorese man came up, young fella, and he said 'now I know what happened to my brother because he disappeared' — so he only found out through this exhibition that we did," Ms Pires said.

The United Nations had an office in Darwin in 1999, which became a focus of protests when violence escalated after the August 30 vote and the world's media had gathered in the city.

Australians for a Free East Timor members showed Gough Whitlam photos of torture in Timor-Leste. ( Supplied: Jude Conway )

Mr Williams controversially launched chickens onto a warship while the UN deliberated about sending a peacekeeping force into Timor-Leste.

The group argued that permission from Indonesia was unnecessary, given the UN had condemned the invasion of Timor-Leste in 1975.

"I got charged for the chicken incident, cruelty to animals, but they were such big, healthy looking chickens," he said.

"We thought they would've been fine and then they would've given them back to us or something."

Cindy Watson, Vaughan Williams, Lurdes Pires and Robert-Wesley Smith protested in Darwin's Raintree Park 20 years ago. ( ABC News: Felicity James )

'They called it propaganda, but we called it the truth'

Ms Pires returned to Timor-Leste a few weeks after the 1999 referendum.

"I was devastated. I spent days looking for families, looking for my friends, looking for people who I had been working with," she said.

"The smell of death, everything was destroyed, there was no water… I can never forget that smell."

The activists set up a makeshift East Timor embassy in Darwin's Raintree Park, where they provided the public with information about what was happening in Timor-Leste.

"We did educate a lot of those UN officials who were definitely told not to come anywhere near us — they called it propaganda but we called it the truth," Ms Watson said.

Darwin's Timor-Leste community held a mass on Friday to remember the August 30 vote and those who died before and after the referendum.

Australians for a Free East Timor members Cindy Watson and Veronica Pereira provided information to the public in 1999. ( Supplied: Vaughan Williams )

Ms Peres said she was proud of Timor-Leste's progress since 1999 but that more women should be recognised for their contribution to the country's independence.

"Women were very strong, some of the people were living in the mountains with the guerilla fighters so they came down to vote," she said.

"Give recognition to women who dedicated their whole lives, it would be nice to see that."