(CNN) The number of asylum claims by Chinese nationals in Australia more than tripled between 2017 and 2018, government figures show, raising fears some applicants are exploiting the system as regular migration visas become harder to get.

According to the Australian Department of Home Affairs, 9,315 Chinese nationals filed for onshore protection visas during the 2017-2018 financial year, compared to 2,269 the year before, an increase of 311% .

The figures suggest that Chinese nationals arriving by plane or those already staying in the country on student and tourist visas are requesting asylum. Malaysian nationals in Australia were the only group to have lodged more onshore asylum claims during the same time period, with 9,319 applications.

One reason for the rise in claims could be "a general increase in Chinese nationals coming to Australia for different reasons, including international students and visitors," Joyce Chia, director of policy at the Refugee Council of Australia, told CNN.

The surge has raised the possibility that unregistered migration agents may be making false claims for asylum on behalf of their clients, or encouraging them to apply for protection visas. There is also speculation that some Chinese could be taking advantage of Australia's slow asylum process to extend their stay.

"For plane arrivals, generally the waiting times (for asylum) have increased enormously in the last few years," said Chia. "We are now talking about averages of years instead of months for people waiting in Australia."

But despite claims of potential abuse, Chia said there are genuine cases of political and religious persecution among the claims.

Chinese authorities have cracked down hard on the country's Uyghur ethnic minority, and have placed them under heavy state-sanctioned surveillance. An estimated one million Uyghurs, a mainly Muslim minority in the country's far west, are being held in detention camps according to a US congressional report.

Australia granted just 10% of all Chinese protection visa claims made between 2017 and 2018 -- one of the lowest success rates for any nationality claiming asylum in the country. But rejected claims may not necessarily mean they were fraudulent.

Transcripts from hearings at the Administrative Appeals Tribunal seen by ABC News indicate a wide range of reasons for applying for protection visas. Some said they had contravened the country's strict family planning laws, were associated with banned religious groups or were members of the LGBT community. All those claims, ABC noted, were rejected for protection visas.

"It's really important that every case be examined on its merits," said Daniel Ghezelbash, senior lecturer at Sydney's Macquarie Law School. "It's dangerous when you start talking about statistics, that you lose sight of the individual."

Chinese students claiming asylum

Chinese tourists and students are an important source of revenue for the government. As of September 2018, there were 652,158 student visa holders in Australia and 30% of those were from China, the biggest cohort from any country, according to figures from the Department of Education.

"It's relatively easy for (Chinese nationals) to get over here," said Ghezelbash. "Australia has a whole bunch of measures in place to keep out people from countries which are likely to apply for asylum. It's very difficult for traditionally refugee-producing countries to get visas to come to Australia. China is an exception to that."

Claimants holding student visas may also have the right to work while their asylum claims are being processed.

"Maybe some people are getting towards the end of their degree and maybe seeing the need to extend their stay in Australia for various reasons. It's difficult to tell from the outside what is going on, but that kind of spike is surprising," said Chia.

Chia warned that any cases of fraudulent claims are worrying because they can undermine the entire asylum system, especially if people are using processing delays as an incentive for making those applications.

"The fact is that numbers of applications are so high and the backlog is so long, it's having an enormous effect on people who are destitute, who are really suffering right now," Chia said.

Restricting visas

The Australian government's hardline immigration policies could also be at play, Ghezelbash said. Australia has made it more difficult to transition from a student visa to other work categories and Prime Minister Scott Morrison's administration has called for limiting overall migration to the country.

"Generally speaking, the more stringent visa requirements become in other categories like work visas or family visas, we see a spike in asylum or humanitarian claims," Ghezelbash said.

Last year Australia overhauled a visa program that allows skilled workers from abroad to hold jobs for up to four years. In November, Morrison refused to sign up to a United Nations migration agreement. And there has been global concern over the country's controversial offshore detention policy for illegal arrivals by boat, with calls for the immediate transfer from Nauru to Australia of children and those needing medical treatment.

In addition to fewer visas, the number of Australian-born residents who were granted citizenship dipped significantly last year. From July 1, 2017, to June 30, 2018,1,720 Chinese nationals were granted citizenship, according to official figures. That compared to around 6,500 during 2016-2017, the Sydney Morning Herald reported.

Ghezelbash said that even if people are gaming the system "it is a necessary evil of having a functioning asylum program."

"You need to have the procedure in place so that people who do need protection can be identified," he said.