Gen. Nguyen Huu Cau, the police chief of Nghe An province where most of the victims were believed to have come from, confirmed that the arrests occurred on Sunday, reports Efe news.
"Based on what we learn from the suspects, we will actively launch investigations to fight and eradicate these rings which bring people illegally to Britain," Cau told the state-run Vietnam News Agency.
Cau said that after the discovery of the truck in England, some agents involved in these networks returned the money they had taken for their services to the families of their missing clients.
Ha Tinh and Nghe An provinces are home to largely rural communities with development levels being lower than other areas of the Southeast Asian nation. Many young people there travel to Europe in search of opportunity.
Vietnamese migrants using irregular channels to travel to Europe pay between $10,000 to $40,000 for the journey, according to a study by anti-trafficking groups.
Meanwhile, a Vietnamese delegation is in the UK and working closely with British authorities to speed up the identification process of the victims.
Initially, police in Essex said the victims, 31 men and eight women, were Chinese, but a number of Vietnamese families have described how they feared that their loved ones were among the dead.
( With inputs from IANS )