(CNN) Imagine working in a foreign country across the world, then getting arbitrarily deported -- but not back to your home.

That's what Taiwan said happened to 45 of its citizens when Kenya forced them onto a plane to mainland China, for no clear reason.

The Taiwanese citizens walked down from a plane in mainland China, their heads covered in opaque black hoods. Each wore a green vest and was flanked by two authorities.

Taiwan calls it the whole ordeal a "gross violation" of human rights. But China praised Kenya, thanking it for supporting the "one China" policy.

It's just the latest twist in a complicated relationship that has turned international.

So how did we get here?

It all started when Kenyan authorities accused a group of Taiwanese workers -- along with some Chinese workers -- of running a complex phone and Internet scamming organization.

The Taiwanese citizens were later acquitted. But when they went to a Nairobi police station last week to pick up their passports, "they were detained by the police for no reason," Taiwan's Ministry of Foreign Affairs said.

Kenyan Interior Ministry spokesman Mwenda Njoka told CNN the Taiwanese were deported as they were in Kenya "illegally."

"If they were here legally we wouldn't have deported them," he said.

Taiwan has vowed to lodge a "solemn protest" with the Kenyans and is demanding an explanation for why its citizens were deported to China.

Taiwanese legislator Johnny Chiang shows a video image from the Kenyan jail cell.

How did Kenya force the Taiwanese to China?

A grainy cellphone video allegedly shot inside a Kenyan jail shows a desperate scene.

Prisoners press their hands and bodies against their cell door, trying to prevent authorities from getting in. A woman's voice warns them to be careful of the armed police outside.

"Sir! We are Taiwan people, Taiwan people!" one man shouts.

Eventually, police used tear gas to force them out of their cell and onto a plane to China, Taiwanese Foreign Ministry official Antonio Chen said.

But Njoka denied that claim.

"It's not true. Why would police tear gas their own station?" he told CNN.

Why did Kenya arrest the Taiwanese after acquittal?

Njoka said Kenyan authorities were following proper protocol.

"We followed international law and released them back to the court in which they came from," he said. "We don't have a relationship with Taiwan as a country, but we have a relationship with China."

He added: "We are being dragged into a diplomatic row that is not ours. China and Taiwan have had their issues with many years. Us, we did our part and we deported them and our story should have ended there. We carried out our obligation as a country."

According to Chinese authorities, in the past some Taiwanese telecom scammers have not been adequately punished.

"Quite a few Taiwan suspects were released as soon as they were returned to Taiwan, and some resumed their wrongdoing soon after," China's Taiwan Affairs Office spokesman An Fengshan said, according to Xinhua.

On Thursday, Taiwan's Minister of Justice Luo Ying-shay said she was aware of the reports, but there was "no solid evidence" that the people deported were involved in fraud.

"This is just an allegation made by China," she said.

Could these prisoners be tried again?

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Yes. An suggested the Taiwanese prisoners would face further prosecution in China, despite being acquitted in Kenya. And in a country that maintains a "one China" policy, An also defended China's right to charge the alleged fraudsters.

"As these criminals carried out their illegal activities abroad, and all the victims are residents of the mainland, the mainland naturally has legal jurisdiction," An said.

But John Chen, a Taiwanese representative tasked with handling the case in Kenya, said that prosecuting the detainees again would be ridiculous.

"For those who have been acquitted by the Kenyan court, they shouldn't be trialed again, because that would be kind of like double jeopardy," he said.

"And for those who are still under investigation in China, they shouldn't be deported to China. If they are to be deported, they should be deported to Taiwan, where they are from, instead of China."

What is Taiwan doing?

"I am not 100% sure about their destiny," said John Chen, the Taiwanese representative in Kenya.

"This is becoming a burning issue in Taiwan. This case of this kind serves as a deterrence for potential Taiwanese visitors or tourists who want to visit Kenya because they would risk being arrested or detained without the legal process."

Taiwanese officials said a delegation would fly to China later this week. However, relatives of the deportees complained of a lack of support or information from authorities in Taiwan.

"I tried several times in the past 15 months to ask the Ministry of Foreign Affairs to help my husband," the wife of one of the deportees told CNN.

She said that her husband had been "helping police with an investigation" and it was not until this week that she heard he was accused of fraud.

The mother of another detainee complained that no Taiwanese officials had been in touch following the news.

"None of them have contacted me. I don't know when I can see my son. I just want him to come back safe and sound as soon as possible."

What is the 'one China' policy?

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The "one China" policy allows both governments to claim sovereignty over mainland China and Taiwan. But, crucially, neither recognizes the other's legitimacy.

Most countries, including the United States, recognize only the People's Republic of China and maintain only limited diplomatic relations with Taiwan -- or none at all.

Chinese Foreign Affairs Ministry spokesman Lu Kang praised what he called Kenya's observance of the "one China" policy.

What's the U.S. connection?

According to Antonio Chen, the Taiwanese foreign affairs official, one of the prisoners deported to China is a dual Taiwanese-U.S. citizen.

While the United States recognizes the "one China" policy, it also sells advanced weapons to Taiwan to defend itself against the larger Chinese military.