Tamil protest rallies have been held in four states without a hint of the ethnic violence feared by sections of Australia’s Sinhalese community, following a violent acid attack earlier this week.

About 300 members of Sydney’s Tamil community gathered in Martin Place and marched to Town Hall to protest the Sri Lankan government’s treatment of civilians held in camps.

Hundreds from Victoria’s Tamil community and their supporters attended a rally in Melbourne and events were also held in Brisbane, Newcastle and Hobart as part of Saturday’s national protest action.

After nearly three decades of civil war, the Sri Lankan government this week declared victory over the Tamil Tigers after its forces finally gained total control over rebel territory.

Hundreds of thousands of Tamil civilians caught up in the long-running conflict have ended up in government camps as its forces advanced on the Tigers.

Some sections of Australia’s Sinhalese community feared the Sydney rally could end in violence – less than a week after a vicious attack on two Sinhalese men, who were doused with acid during a home invasion.

Police have said at least five men smashed their way into the pair’s Westmead home last Sunday night.

The attack was thought to have been a reaction to the Tamil Tigers finally admitting defeat.

Sam Pari, a spokesman for Australia’s Tamil community, said about 80 rallies had been held across the country in recent months, and all of them had been peaceful.

Even so, a handful of police were on hand to monitor Saturday’s protest.

“I’m confident that the Australia Tamil community had nothing to do with that violence (the acid attack),” Ms Pari said.

“The incident that took place was between individuals who cannot control their actions.

“We’ve had 70 to 80 rallies across Australia in the past few months, and none of them have seen any violence.”

Ms Pari said the protesters were calling on the Australian government to cut trade and aid ties with Sri Lanka.

They were campaigning for unimpeded access for relief agencies, journalists and human rights monitors, plus an investigation into war crimes and the establishment of a Tamil state, she said.

During a visit to the war-torn country on Saturday, UN Secretary-General Ban Ki-moon urged the Sri Lankan government to allow “unimpeded access” to the camps.

Ms Pari said although the Sri Lankan government said the military onslaught had ceased, it was still not allowing the United Nations, aid agencies or the media into the camps where 300,000 Tamils are hiding.

“Australia should really step up and pressure Sri Lanka, and the only way to do that is to cut trade links,” she said.

“Australia should also stop any aid reaching Sri Lanka.”

Foreign Minister Stephen Smith also called on Saturday for greater access to the camps for the UN and aid agencies.

“This is not a problem or an issue which Sri Lanka can deal with by itself without the assistance of the international community,” Mr Smith told ABC Radio.

“There needs to be access for the usual United Nations and international agencies who are best placed to render assistance in these very difficult circumstances.”