BEIJING/TAIPEI: A Beijing court on Thursday handed down jail sentences of up to 15 years to 85 people deported from Kenya for telecoms fraud, including 44 from self-ruled Taiwan, an island Beijing claims as its own which said vital evidence had been ignored.

Over the past two years, countries including Kenya, Spain, Vietnam and Cambodia have deported hundreds of people from Taiwan to China for telecoms fraud, sparking accusations from Taipei that Beijing was effectively kidnapping its citizens.

China has defended the deportations, saying the crimes were committed against people in China and that as Taiwan is a part of China.

The Beijing court said in a statement that one of the Taiwanese, Chang Kai-min, had been jailed for 15 years for helping scam 185 people out of more than 29 million yuan ($4.4 million).

Taiwan's China policy-making Mainland Affairs Council said Taiwan and China had initially agreed to cooperate in investigating the Kenya case, but China had gone back on its word.

The outside world could only believe justice had been done if the case had fully considered all the evidence and gone through proper legal procedure, the council added.

"In this case, we obtained intelligence on the criminal suspects behind the scenes," it said.

"We again call on the mainland China side to cooperate with our public security organs, investigate the origins and not allow the masterminds behind the scenes to get away with it."

On at least two occasions last year, Kenya deported groups of Taiwanese to China. In one case, a Kenyan magistrate said the Taiwanese should be repatriated to their place of origin, Taiwan, but the Kenyan government sent them to China.

Kenya, like most countries, only has diplomatic relations with China. Beijing considers democratic Taiwan a wayward province, ineligible for formal ties with other nations.

Chinese authorities have sought to contain an explosion of telecom crime it says has led to huge financial losses, with callers often impersonating officials or authority figures and preying on the elderly, students or the unemployed.

The fraud has spread overseas, with Chinese speakers recruited in neighbouring Taiwan increasingly setting up operations in East Africa or Southeast Asia.

The deportations have come as relations between Beijing and Taipei have deteriorated, with China suspecting Taiwan President Tsai Ing-wen of pushing for the island's formal independence.

She says she wants to maintain peace with China but will defend Taiwan's security and democracy.