Video caption Thirty nine bodies were found inside the trailer

Police have begun the process of trying to identify 39 bodies found in a refrigerated lorry trailer in Essex.

The trailer arrived in Purfleet on the River Thames from Zeebrugge, Belgium, at about 00:30 BST.

Ambulance staff discovered the bodies in the unit just over an hour later at Waterglade Industrial Park in Grays.

The lorry driver, named locally as Mo Robinson, 25, from Portadown, County Armagh, Northern Ireland, is being questioned by police.

Deputy Chief Constable of Essex Police Pippa Mills said the vehicle had been moved to a secure site at Tilbury Docks so the bodies of the 38 adults and one teenager could be "recovered while preserving the dignity of the victims".

She said identifying the deceased remained a "priority" butwas expected to be a "lengthy process".

Meanwhile, officers from the Police Service of Northern Ireland have carried out raids on two houses associated with the arrested man - one in Markethill, County Armagh, and another in nearby Laurelvale.

Image copyright Facebook Image caption The lorry driver has been named locally as Mo Robinson, from Northern Ireland

Police said the tractor unit (the front part of the lorry) came from Northern Ireland and picked up the trailer from Purfleet.

The tractor and trailer then left the port shortly after 01:05 and officers were called around 30 minutes later when ambulance staff made the grim discovery.

Police have appealed for witnesses and anyone with information about the lorry's route to contact them.

The National Crime Agency said it had sent officers to assist and identify