nytimes_NGHIA BINH, Vietnam — Growing up in this village of rice paddies and banana trees, Doan Thi Huong was known as a gentle girl and a diligent student, her brother said.
She left home at 17 to study pharmacology in Hanoi, the capital, and has returned home only about twice a year in the decade since, said her brother, Doan Van Binh. He said that he rarely pressed his sister for details about her life, and did not realize until a few days ago that she had been working in Malaysia.
“I only hoped she was well,” Mr. Binh said in an interview on Thursday.
Instead, to her family’s shock, Ms. Huong is a prime suspect in the Feb. 13 killing of Kim Jong-nam, the half brother of the North Korean leader, Kim Jong-un, at the airport for Kuala Lumpur, Malaysia. The Malaysian authorities said Friday that Ms. Huong and an Indonesian woman, Siti Aisyah, both of whom are in detention, had applied a lethal nerve agent to Mr. Kim’s face.
But until her life took that bizarre turn, Ms. Huong’s story appears to have been a very familiar one.
A 28-year-old whom Malaysian police officials have described as an “entertainment outlet employee,” Ms. Huong was one of millions of Southeast Asians working overseas, in many cases off the books. More than 18 million people from the region were working abroad in 2013, according to United Nations data.
Ms. Huong’s Facebook page suggests that she led a peripatetic lifestyle, moving between hotel rooms in Cambodia and Malaysia in recent weeks. While stressing that they had no information about Ms. Huong’s particular situation, experts said that Vietnamese women who work as escorts, masseuses, prostitutes and waitresses in Southeast Asia’s wealthier cities, particularly Singapore and Kuala Lumpur, often follow a similar pattern of movement.
Ms. Huong’s posts from Malaysia, which showed her smiling coyly in portraits and videos, hardly seemed those of a hardened assassin. Photos showed ice cream, chicken wings and a smiling gray teddy bear propped up on a hotel bed.
“Life is food,” Ms. Huong wrote in one post under her alias, Ruby Ruby. “I can eat very much.”
Nghia Binh, Ms. Huong’s hometown, lies in the Red River Delta, a largely agricultural, densely populated region in northern Vietnam that has severe unemployment. Hundreds of thousands of workers from the delta and other regions have emigrated to Japan, Malaysia, South Korean and Taiwan in recent years.
As the delta’s population expands, “there are very few viable employment opportunities” beyond farming, said Lan Anh Hoang, a senior lecturer in development studies at the University of Melbourne in Australia who has studied Vietnamese labor migration extensively. “So labor migration overseas seems like the obvious choice for many.”
Malaysia hosted nearly 2.5 million international migrants in 2013, according to the United Nations data, making it the largest destination for migrant workers after Thailand in the Association of Southeast Asian Nations, a group of 10 countries with a combined population of more than 600 million.
Many migrants, including tens of thousands of Vietnamese, travel to Malaysia through formal labor contracts that are governed by state quotas and arranged through accredited labor brokerages.
But that process can be corrupt, exploitative and expensive, requiring workers to pay thousands of dollars to brokers, experts say. One result is that some immigrants leave their jobs to work in the shadow economy, or bypass formal contracts altogether.
As much as Southeast Asian governments try to regulate flows of migrants across their borders, “there will always be people who fall into the cracks,” said Ellene A. Sana, the executive director for the Center for Migrant Advocacy in Manila.
Because Vietnamese are permitted to travel without visas in Singapore and Malaysia for 30 days at a time, many Vietnamese escorts and prostitutes travel in a constant loop through the three countries, said Nicolas Lainez, an anthropologist in Singapore with the Paris-based School for Advanced Studies in the Social Sciences.
The lifestyle appeals to them, Mr. Lainez said, because the working schedules offer flexibility as well as a higher income — from about $700 to $7,000 per month, compared with just a few hundred dollars for a job on a factory assembly line.
Ms. Huong’s Facebook photographs and the attached location information indicated that she had visited Malaysia twice this year — first in early January and again in early February, days before Kim Jong-nam was killed.
Her Facebook page, which appears to have been shut down, had shown no sign of Nghia Binh, her hometown. But her father, Doan Van Thanh, said that she visited the village during the Tet holiday that began in late January.
Mr. Thanh said that when Ms. Huong arrived, she was short of money and came bearing only one gift: a bonsai plant worth 100,000 Vietnamese dong, or about $5. She also asked her stepmother, Mr. Thanh’s wife, for a loan of 50,000 dong. “She didn’t tell me anything about going abroad,” he said.
Her brother, Mr. Binh, said that he was still struggling to digest the news that Ms. Huong, who had never been a quarrelsome sibling, was now a murder suspect.
“She loves everyone,” he said, “and everyone loves her.”