The lorry containing 39 bodies discovered in South-East England this morning is registered in Bulgaria by a company owned by an Irish citizen.
A teenager is among those who were found dead in a container at an industrial park in Essex.
Gardai are investigating if the truck travelled from Bulgaria through Dublin Port en route to Holyhead on Saturday.
The first picture has emerged of the lorry driver believed to have been arrested by police after 39 bodies were found in a lorry.
The man has been named locally as Mo Robinson, a 25-year-old from Portadown.
He is being held on suspicion of murder after the grim discovery at Waterglade Industrial Park in Grays, Essex, at 1.40am this morning.
Detectives now believe the truck had travelled from Zeebrugge, Belgium, into the port of Purfleet, Essex.
It then docked in the Thurrock area at around 12:30am local time for around 35 minutes before departing.
The horrific find has sparked one of the biggest murder investigations in British history – and was described by Essex Police as an ‘absolute tragedy’.
Essex Police has launched a murder investigation after the bodies of 39 people were found inside a lorry container in Grays. https://t.co/NhmGRDEzNO
— Essex Police (@EssexPoliceUK) October 23, 2019