The Chinese nationals, whose identities have not been disclosed, were arrested by Vanuatu police in a night raid two weeks ago, prompting local media and observers to suggest it was a sign of Beijing's growing influence over the country.
On Friday, the group were escorted to an unmarked plane, each suspect flanked by a police officer - a Vanuatu one holding one arm, a Chinese officer the other, neither in uniform - and sent to China, the Vanuatu Daily Post newspaper reported.
None of the suspects appeared in a Vanuatu court or had the process to appeal against their deportation. At least four of the people were reported to hold a Vanuatu passport, which would normally afford them an extradition process.
The internal affairs minister, Andrew Napuat, told RNZ Pacific that Vanuatu was aware the six were wanted and moved to deport them without warning, but had been unable to because of a lack of direct flights to China.
"What we did here was a normal operation that was conducted by immigration and the Vanuatu police force," said Mr Napuat, stressing that Chinese police had not played a direct role in the arrests and detention of the suspects.
He said Vanuatu authorities were shown arrest warrants by Chinese officials but had not been told if any charges had been laid or what crime the people were alleged to have committed.
The hasty operation comes as Vanuatu struggles with an influx of either criminal or trafficked migrants.
Since November, the government has been housing dozens of Bangladeshi migrants who were trafficked to Vanuatu over two years. With the help of the International Organisation for Migration, it has managed to send back some of the men back to Bangladesh in recent weeks.
"We're paying for their rent within for the food, we're paying for everything for their stay here. And that's essentially the situation, because if we continue to delay ... the government is going to be incurring costs that was not budgeted for," said Mr Napuat.
Still, observers were quick to point out the similarities from last Friday's deportations to those of a similar case in Fiji.
In 2017, a group of 77 Chinese nationals who were said to be part of an online fraud syndicate were rounded up and returned by Chinese police on a chartered flight. Dramatic images showed the suspects - none of whom held Fijian passports - hooded and flanked by uniformed police, in an operation led and coordinated by China.
A Vanuatu Foreign Ministry official said at the time the same thing could not happen in Vanuatu.
"Has something changed since then, that has allowed for what on the surface looks like a very similar set of circumstances to now be able to eventuate, when we've been told nearly two years ago that that would never be possible?" asked Tess Newton Cain, an analyst with TNC Consulting.
Mr Napuat denied there were similarities between the Fiji and Vanuatu deportation cases. He also criticised the portrayal of last week's deportations by the Daily Post, which said in an article that "under a veil of secrecy, China has convinced Vanuatu to enforce Chinese law within its own borders".
On Monday, the newspaper posted an editorial demanding the government answer several questions, including if the detainees were given access to legal counsel.
"I'd like to know the names of the people who were arrested, the crimes that they're charged with, and what is going to happen to them now that they've been returned to China," the Daily Post's news director, Dan McGarry, said in an interview.
"None of these questions have been answered."
The Chinese embassy in Vanuatu did not respond to requests for comment.