Police in the northern province of Lai Chau said they are investigating three people suspeted of attempting to smuggle a 13-year-old girl into China.
Police announced on Thursday, that hey had found that Hoang Thi Loan, 43, who has been previously convicted for human trafficking, returned to Cap Na Village from China on November 5.
She then met with Luong Thi Than, also 43, and asked the woman once convicted of drug trafficking to seek out some local girls so that she could sell them to China.
Most local girls had left the village to work, police said, so Than targeted Luong Thi Thai, who suffers from mental disorders.
Loan agreed to pay Than VND15 million (US$769.42) for the transaction, police said.
Than's daughters, 16-year-old Lo Thi Ngoc and 15-year-old Lo Hoa Ut, also joined it, they added.
On November 7, Than hired a xe om for Ngoc and Ut to bring Thai to the adjacent Lao Cai, telling the girl's family that she would be given a job washing dishes and cleaning homes there, according to police.
Loan was arrested while transporting Thai to China.
Lai Chau police said they are currently keeping Loan, Than and Ngoc in custody for their investigation. Ut, meanwhile, has been handed over to local authorities because she is still under age.