Australia sends back Sri Lankan asylum seekers

Australia's immigration minister says a group of asylum seekers who reached the country's Cocos Islands territory last week has been sent back to Sri Lanka.

The vessel, carrying 12 people, came within 500m of Home Island.

Immigration Minister Peter Dutton said the asylum seekers, all Sri Lankans, were returned on 6 May.

He also announced that Australia had intercepted three asylum boats so far this year, but did not provide details on the other two boats.

The Cocos Islands are a remote chain of islands and atolls located between Sri Lanka and the west coast of the Australian mainland.

The announcement was made on Monday, the first official day of Australia's federal election campaign.

The number of asylum seekers coming to Australia by sea has plunged due to tough policies such as offshore processing and boat tow-backs.

Mr Dutton used his press conference to criticise the opposition Labor party's position on securing Australia's borders.

On Monday a Labor MP, Sophie Ismail, said she had concerns about Australia's controversial immigration policies.

"I have concerns about turn-backs, I don't think they should be on the table," Ms Ismail said, according to media reports.

"When people arrive by boat, and 90% of them are genuine refugees, turning them back to places not signed up to the refugee convention is problem," she said.

Mr Dutton said these comments showed that the Labor party was "split" in regards to immigration policy.

This was disputed by opposition leader Bill Shorten.

"One thing I will never do is put the people smugglers back in business," Mr Shorten said in a television interview, indicating many of Australia's policies would remain unchanged if Labor won the election.

Meanwhile, Mr Dutton also revealed the fate of asylum seekers held at Australia's detention facility on Manus Island in Papua New Guinea would not be decided for months.

Papua New Guinea's supreme court recently ruled that the facility was "illegal" under its constitution.

"I think it will be a couple of months to sort through legal issues," Mr Dutton said, meaning the decision would come after the 2 July election.

Australia sends intercepted asylum seekers to offshore locations Manus Island and Nauru.

The government says the journey asylum seekers make is dangerous and controlled by criminal gangs, and they have a duty to stop it.

However, critics say opposition to asylum is racially motivated and is damaging Australia's reputation.

Two asylum seekers on Nauru recently set themselves on fire, including a 23-year-old man who died of his injuries.