TAIPEI (AFP) - Nearly one hundred Taiwanese suspected of running telephone scams have been arrested in Slovenia and Croatia, Taiwan said on Thursday (Jan 25), the latest fraud bust involving the island's citizens.

Taiwanese crime rings around the world have for years swindled billions of dollars through the scams, with many of the victims Chinese.

The arrests are likely to heighten cross-strait tensions as Beijing insists that all arrested Taiwanese fraudsters be deported to China.

It came after Poland last week said it had arrested 48 Taiwanese and two Poles who extorted around €1.8 million (S$2.9 million) in a year from Chinese nationals by pretending to be from the local police on the phone.

Taiwan's Foreign Ministry said on Thursday that 36 of its citizens were held by Slovenian police, while 61 Taiwanese were detained in Croatia.

The arrests were a joint effort by the two countries and the Chinese police, according to media reports.

Beijing sees self-ruled Taiwan as part of its territory, but Taiwan's President Tsai Ing-wen has refused to acknowledge this, causing relations to deteriorate rapidly since she came to power in May 2016.

Countries from Spain to Indonesia have agreed to deport Taiwanese scammers to China despite protests from Taipei, which says the suspects should be sent back to Taiwan for investigation and trial.

Last month, China jailed 44 Taiwanese for telecom fraud after they were extradited from Kenya. The heaviest sentence was 15 years.