The Vietnamese Embassy in Angola has asked the country's police and Ministry of Interior to investigate alleged murders of three Vietnamese workers in two separate cases.
On February 17, Tran Xuan Hoa, 43, from Vietnam's northern province of Hai Duong, was killed at the construction site where he worked in the capital Luanda. The name of the contractor, a Brazilian company, has not been released yet.
Nguyen Thi Hai, 35, and Nguyen Thi Xuan, 31, both from the north-central province of Ha Tinh were then killed on February 24 at their rented home 20 kilometers from Luanda.
Hai and Xuan had paid brokers to go to Angola to cook for workers at construction sites but suspicions have been raised that the women were forced to work as prostitutes instead.
The women's families on Monday sent notes to the two countries' Ministries of Public Security and Embassies to clarify the cause of their deaths.
All the three were undocumented workers who had come to Angola with tourist visas.
Pham Tien Nhien, the Vietnam ambassador in Angola, told Thanh Nien on Sunday that Hoa had been shot by construction site guards on a rainy night. "Hoa had used a notice board at the site to cover his head. Then I don't know if there was any argument."
He said Angolan laws do not allow non-military forces to use guns.
"The construction site managers have to make an apology," he said.
In a note sent to Angola's Department of Criminal Investigation Police and Ministry of Interior, the Vietnamese Embassy also asked the contractor to compensate Hoa's family and explain his death clearly.
Hai and Xuan were found stabbed to death in the backyard of their rented home in Genna city. There were blood stains inside their house and the house had been thoroughly ransacked.
Their personal papers, cash and other assets were all taken, according to a source from the Association of Vietnamese People in Angola.
Xuan's younger brother, Nguyen Van Ha, told Thanh Nien Xuan had called home several times saying that she had been forced to sell sex and was beaten if she refused to do so.
He also said that Xuan had called home a couple of days before her death to inform that she would send home US$6,000. The family couldn't contact her after that, he said.
"When my sister's body was brought home, my family opened part of the coffin and saw a very deep cut across her parotid and many others over her face."
Hai had called home several times to tell about her hard life and her attempts to escape, said her brother Nguyen Van Trung.
"There are many things still unclear about my sister's death. We need concerned agencies to clarify the situation and the role of the people that forced my sister into prostitution."
Three victims were brought back home and buried last Saturday. Hoa came to Angola as a tourist and has worked there for more than one year. Xuan had been in Angola for eight months and Hai less than four.
Tuyet, a broker who introduced Hai and Xuan to jobs in Angola, has been detained by Angola authorities to provide information concerning the victims. Tuyet is from the north-central province of Ha Tinh and has opened her own business in Angola.
Ambassador Nhien said the cases were rare as Vietnamese people in Angola have previously lived in "good" security.
But as most of them were working there with tourism visas rather than a work permit, he said it was difficult for the Vietnamese Association in Angola to intervene and help them out of bad situations.
Dao Cong Hai, deputy head of the Overseas Labor Management Department at Vietnam's Ministry of Labor, War Invalids and Social Affairs, said on Monday that no business had been granted permits to recruit laborers for the Angolan market.