New Year's Day marks the anniversary of an early attack on Australian soil motivated by events in foreign warzones and the nation's relationship with the Middle East.

On New Year's Day 1915, two members of Broken Hill's migrant cameleer community brandishing a Turkish flag opened fire on a trainload of picnic-goers near Broken Hill.

About 1,200 locals had crowded onto open-roofed train carriages to travel to a picnic in the nearby small town of Silverton for the first day of the year.

But just a few kilometres out of town, shots were fired from behind an ice cream truck parked railside and sparked a series of events that would see six people killed and another seven injured.

Christine Adams from Broken Hill's Railway and Historical Museum said the crowd was initially confused.

"For a few seconds they ... thought that it was part of the celebration of New Year's Day and then they saw, you know, a couple of people had gone down in the wagons [and were] bleeding," she said.

I will fight and kill your people: attacker

Police said a letter found on the younger man, an ice cream vendor named Gool Mahomet, stated he was a subject of the Ottoman Sultan.

"I will fight and kill your people, because your people are fighting my country," the letter read.

Just a few months earlier the Ottoman Empire had joined World War I with Germany against the British, and it was thought that the war was a motivation for the two gunmen, but the situation was more complex.

Ms Adams said, from all accounts, life in the area was difficult for the gunmen.

Broken Hill's picnic train pictured after the attack. ( Supplied )

"I'm sure that he and the older man had their own perceived grievances of how they were treated," she said.

"The White Australia Policy was still in vogue. They didn't have a very good life here.

"If you read earlier accounts of the way they were described by the local media, it was pretty horrific."

The older gunman, a butcher named Mullah Abdullah, said his target was the town's inspector who harassed him for butchering meat without a proper license.

Cameleers refuse to bury bodies of gunmen

Bobby Shamroze is a descendent of Broken Hill's Afghan cameleers and caretaker of the city's tiny tin mosque - the oldest in New South Wales.

"From what I've read there's one bloke [who] had a bit of a blue with the health inspector about killing the meat. [He] probably thought it wasn't healthy back in them days," he said.

"I don't know [but] from what I can gather one was only a young bloke and the other bloke was an older bloke and he was supposed to be a bit silly.

"And they must have just went off their head and started shooting."

Mr Shamroze said the Broken Hill cameleers refused to bury the bodies of the two gunmen after the attack.

"They never had nothing to do with it. They weren't the ones who'd done it. It was just these two," he said.

"I don't know what you'd call them [they are] just two blokes that just went off the rails and took things into their own hands."

Victim's family gathers on New Year's Day

Riflemen returned to Broken Hill after the attack. ( Supplied )

Alma Cowie, 17, was the first of six people who were killed in the shooting including the two gunmen who were shot by police.

On Thursday morning, nearly 100 of Alma's descendents and relatives attended the commemorations at Broken Hill's railway museum, including some of Alma's nieces.

Her 100 relatives, including niece Peggy Corney, visited 100 years after she was buried.

"Really this weekend for all of us [is], I think one of the headlines was 'remembering Alma', and that's what we're all about really, just that," Ms Corney said.

"And getting to meet rellies we haven't met before."