The 39 people found dead in the back of a lorry in Essex were all Chinese nationals, it has been reported.
Police have searched two addresses in Northern Ireland connected to the driver - 25-year-old Mo Robinson from Northern Ireland, as the National Crime Agency works towards identifying "organised crime groups who may have played a part".
He remains in custody for questioning on "suspicion of murder".
It comes as Belgian authorities continue to investigate the journey of the lorry where the bodies were found.

Evacuated residents of Oleshky arrive in Ukraine, Zelenskiy says
Congo Ebola outbreak kills more than 5,000
Isolated clashes in France, as tensions erupt after peaceful marches
Residents of Russian-controlled Ukrainian town arrive in Belarus
