The deputy leader of a banned opposition party in Cambodia was arrested in Malaysia on Thursday, according to Human Rights Watch.

Mu Sochua, vice president of the Cambodia National Rescue Party (CNRP), was detained by officials upon arrival at Kuala Lumpur airport after flying in from the Indonesian capital of Jakarta, said Phil Robertson, the deputy director for Human Rights Watch in Asia.

65-year-old Sochua flew into Kuala Lumpur on her US passport and was being held for questioning at the airport. Officials had yet to decide whether to deport her to Cambodia to face trial.

Malaysian foreign minister Saifuddin Abdullah told reporters: "We have received a request, but we decide on our own."

Later on Thursday, Malaysian Prime Minister Mahathir Mohamad told reporters authorities were seeking a third country with which to send Sochua to.

"Our principle, in ASEAN in particular, generally is that we don't interfere in the internal affairs of other countries," Mahathir said referring to  the Association of Southeast Asian Nations.

"We do not want to let them to use Malaysia as a base for struggle in other countries. We wanted to deport her ... now we are trying to find any country that can take her."

Honoring ASEAN ties

The decision to detain Sochua in Kuala Lumpur would appear to be a show of unity among several Asian countries, after Thai Prime Minister Prayuth Chan-ocha on Wednesday promised to block moves by CNRP's leader, Sam Rainsy, to return.

When asked by reporters about Rainsy, who has bought a plane ticket for Saturday to Bangkok, Prayuth said: "According to our commitment to ASEAN, we will not allow an anti-government person to use Thailand for activism. I have ordered this, so he probably won't get in."

Blocked from boarding

The Thai premier's promise seemed to come to fruition as Rainsy confirmed to reporters he was prevented from boarding his Bangkok-bound flight with Thai Airways.

Rainsy told news agency Reuters at Paris' Charles de Gaulle Airport that flight crew had refused to let him board, but that he would not be deterred from trying again.

"I'm not allowed to board. They said they have received from very high up the instruction not to allow me to board. I'm very shocked, I'm very disappointed. I want to go back, my people are waiting for me."

NGO criticizes arrest

Sochua's arrest at Kuala Lumpur airport drew a stinging rebuke from Human Rights Watch, describing it as "ludicrous and unacceptable."

The non-governmental organization added: "She's done nothing wrong and should be immediately released and allowed to undertake the consultations she planned with the Malaysia government and civil society groups."

Political rivals

Rainsy said he plans to lead a "people-power" movement to usurp longtime Prime Minister Hun Sen, but the Cambodian government has said this would be tantamount to a coup attempt. Officials have promised to arrest CNRP leaders upon arrival.

For over two decades, Rainsy has been Hun Sen's principal political opponent. In the general elections of 2013, CNRP came a close second, winning 55 of the 123 parliamentary seats. During commune elections in 2017, the opposition party repeated that result, when it won almost 44% of all the votes.

However, later in 2017, the CNRP ran into trouble when co-founder Kem Sokha was arrested on charges of treason. The controversial case against Sokha was enough for the Supreme Court to dissolve the CNRP in November of the same year.

Without the main opposition party contesting the elections, Hun Sen led his Cambodian People's Party (CPP) to victory the following year in a vote that at the time was described as a "sham." The CPP won every seat in the parliament, turning the Southeast Asian country into a one-party state.

jsi/rt (AP, Reuters, dpa)

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