In a statement, Taiwan's Ministry of Foreign Affairs denounced the incident as an "extrajudicial abduction."
Asked about the incident in a regular news conference, China's Ministry of Foreign Affairs spokesman Lu Kang said that "the one China policy is an important precondition for bilateral relations with China and other countries. We commend Kenya for implementing this policy."
The "one China
" policy is the principle by which both governments claim sovereignty over mainland China and Taiwan -- but crucially neither recognizes the other's legitimacy.
Kenya does not recognize Taiwan -- officially the Republic of China -- nor does it maintain diplomatic relations with the island.
Taiwanese officials said Beijing and Taipei set up a hotline to deal with the issue, which involves two groups of detentions last week. A Chinese official suggested Wednesday the Taiwanese may face prosecution in China for the crimes they were acquitted of in Kenya.
Acquitted, then deported
The alleged abduction comes after a protracted legal affair in Kenya involving both Chinese and Taiwanese workers in the country who had been accused of running a complex phone and Internet scamming organization.
"When the first batch of 37 defendants acquitted by the court -- which included 23 Taiwanese -- went to a local police station in the Kilimani area of Nairobi on Tuesday last week to retrieve their passports, they were detained by the police for no reason," the Taiwanese statement said.
The ministry said that over the objections of its consular staff in the country, and a Kenyan High Court's injunction banning police from deporting the Taiwanese pending a hearing, China made use of a "technical obstruction" to put eight of the 23 workers on a flight out of the country last Friday.
"By the time our official rushed to the airport, the eight Taiwan citizens had been forcefully taken to a passenger plane of China Southern Airlines and sent to the mainland," it said.
Antonio C.S. Chen, the Taiwan Foreign Ministry's chief of West Asian and African affairs, told reporters Tuesday that 37 Taiwanese nationals, including the remaining 15 from the first detention, were sent to mainland China that day. He accused Kenyan officials of using forcible means -- such as tear gas -- to get many of the nationals to comply with the deportation.
He said one of the people who was deported is a citizen of both Taiwan and the United States.
Taiwan has learned that the initial eight deportees are being held at a detention center in Beijing.
Speaking at a regular press conference, China's Taiwan Affairs Office spokesman An Fengshan seemed to suggest those deported to China may face prosecution there, despite being acquitted of the alleged fraud in Kenya.
"As these criminals carried out their illegal activities abroad, and all the victims are residents on the mainland, the mainland naturally has legal jurisdiction."
He added that the incident would be "beneficial to the peaceful development of cross-strait relations."
Taiwan has contacted Chinese authorities to demand the return of its citizens, Mainland Affairs Council Deputy Minister Shih Hui-fen told lawmakers during a legislative hearing on Monday.
The procedure violates a "common understanding" on both sides of the Taiwanese strait, Shih said.
Cross-strait relations have been strained in recent months following the landslide election of Tsai Ying-wen as Taiwan's next president
Tsai is leader of the Democratic Progressive Party, which has traditionally leaned in favor of formal independence for the island from mainland China. Beijing views Taiwan as an integral part of its territory.
Taiwan also recently waded into the contentious South China Sea territorial dispute
, with outgoing President Ma Ying-jeou last month inviting reporters to the tiny Taiping Island in the Spratlys chain, which is claimed by six countries.
Taiping Island "is entitled to an exclusive economic zone of 200 nautical miles," Ma said -- which gives a country special rights over the seabed, and marine resources like fish.