Indonesian police have arrested more than 100 Taiwanese at a villa in Bali over alleged cyber fraud, authorities said Friday.

The proliferation of cyber fraud groups in Southeast Asia has become a growing concern in recent years, and authorities in countries including China, Indonesia and Malaysia have stepped up efforts to stop them.

Bali immigration authorities said that after a tip-off from Indonesian police, they raided the villa in Tabanan Regency on Wednesday, where the group of 12 women and 91 men was found with hundreds of mobile phones and other electronic devices.

They were accused of abusing immigration permits and conducting online scams targeting Malaysians, said Indonesian immigration official Safar Muhammad Godam.

He added that officials could not charge them because the alleged crimes fell outside their jurisdiction, but were "closely working together" with related authorities, including those in Malaysia.

"Their activities target individuals outside the country, making it very difficult to meet the elements of a criminal offence in such cases," Godam said in a press conference.

"They are subject to administrative immigration actions. In the near future, we will proceed with deporting all of the 103 foreign nationals."

They are currently being held at an immigration detention centre in Bali for further questioning, he added.

Indonesia, with tip-offs from Chinese authorities, has previously confronted international cyber fraud networks targeting victims in China.

In 2018, Bali Police arrested 103 Chinese nationals, along with 11 Indonesians allegedly working for them, for running a multi-million-dollar cyber fraud syndicate that targeted wealthy businessmen and politicians in China.

This came a year after the deportation of 153 Chinese nationals involved in a network accused of fraudulently impersonating Chinese police or law officials, making around six trillion rupiah ($365.5 million) since launching operations in late 2016.