British police initially said all 31 men and eight women found in a lorry in an industrial park in Essex this week were believed to be Chinese.
Northern Ireland trucker Mo Robinson was accused of being part of "a global ring" when he appeared in court over the alleged manslaughter of 39 migrants who were found dead in a trailer in Essex.
A man and woman, both 38, from Warrington were arrested in Cheshire on Friday October 25 and a 46-year-old man from Northern Ireland was arrested at Stansted Airport later the same day.
Families face an agonising wait to find out if their loved ones were among the dead after Essex Police launched "the largest mass fatality victim identification process" in the force's history.
The 25-year-old appeared via video link at Chelmsford Magistrates' Court today.
Robinson is charged with 39 counts of manslaughter of persons unknown, conspiracy to traffic people between December 1 2018 and October 24 2019 and conspiracy to assist unlawful immigration between the same dates.
Three others arrested within the investigation have been launched on bail till subsequent month, Essex Police have mentioned.
United Kingdom police said Saturday that all 39 victims were out of the truck and in a mortuary awaiting autopsies.
Britain's prime minister has signed a condolence book honoring the 39 people who died in a refrigerated truck container in southeastern England last week.
In Vietnam, relatives of Bui Thi Nhung, aged 19, expressed fears she may be among the dead.
The father of one young woman feared to have died said her family tried to talk her out of the journey.
Maurice Robinson, 25, of Craigavon in Northern Ireland, is due to appear via videolink at Chelmsford Magistrates' Court.
Gravett likened the activities of people traffickers to the operations of the Amazon website, with their network made up of "a host of resellers" working together.
But several Vietnamese families have come forward saying their relatives went missing on route to Britain, a prime destination for Vietnamese migrants seeking better lives overseas.
Geng also said Monday that reports that the victims had Chinese passports was "speculation".
"I'm so sorry mom and dad.My journey overseas doesn't succeed", she wrote.
Police have found more than 500 items within the lorry including bags, clothing and mobile phones that need to be assessed.
In Vietnam, family and friends of those believed missing have gathered at homes to pray for their loved ones. I'm dying because I can't breathe.
Vietnam's ambassador, Tran Ngoc An, visited police investigating the case on Saturday and also spoke on the phone to British interior minister Priti Patel, the embassy said.
"Police from the Ministry of Public Security came to get DNA samples, our hair and blood", Nguyen Dinh Gia told Reuters at Can Loc in Ha Tinh province, where sympathisers gathered at the simple house amid lush rice fields to console the family.
Many work illegally in nail bars or cannabis farms, heavily indebted and vulnerable to exploitation.