The 39 migrants found dead in a refrigerated lorry were all Chinese nationals.

A murder investigation was launched after 39 bodies were found inside a lorry container near the Dartford Crossing.

Essex Police headed to the Waterglade Industrial Park, Eastern Avenue, Grays, on the other side of the River Thames in the early hours of yesterday, where the bodies were found.

Detectives have now confirmed 31 of the migrants were men and eight were women, one of whom who was previously thought to be a teenager was in fact a young adult. They were all Chinese.

The development means the horrific case echoes even more with the death of 58 Chinese migrants, found in the back of a lorry at Dover in 2000.

The tractor unit of the lorry entered the country via Holyhead, Wales, on Sunday, having travelled over from Dublin.

It collected the trailer, which had travelled from Zeebrugge, at the port of Purfleet at around 12:30am on the 23 October. The cab and trailer left the port shortly after 1am.

Police were called to the industrial estate shortly before 1.40am by paramedics.

The lorry has since been removed from the industrial park and taken to a secure site at nearby Tilbury Docks.

An escort will take the first convoy to the mortuary in Broomfield Hospital, Chelmsford at 4pm where post-mortems of the victims will be carried out.

A police cordon remains in place at both entrances to the business park this afternoon while investigations are ongoing.

Officers continue to question the lorry driver, a 25-year-old man from Northern Ireland, who has been arrested on suspicion of murder. They were granted longer to do so this afternoon.

Three properties in County Armagh have been searched in connection with the investigation.

A police statement released this morning read: "Each of the 39 people must undergo a full coroner’s process to establish a cause of death, before we move on to attempting to identify each individual within the trailer. This will be a substantial operation and, at this stage, we cannot estimate how long these procedures will take.

"Local residents and businesses have shown us the utmost kindness and respect as we deal with this difficult and sensitive investigation.

"Thank you for patience, your offers for cups of tea for our hardworking teams, for the flowers that have started to appear in Eastern Avenue, and the signatures we know will appear in the Book of Condolences at the Civic Centre.

"We would also like to thank all of our local and national partners for their assistance and support, especially the Red Cross who gave our officers a quiet place to go when they needed a moment, and Thurrock Council who have continued to help us ensure that disruption to the local community is minimal.

"We will continue to work with partners and other law enforcement agencies to establish exactly how these 39 people lost their lives in such an untimely way.

"This process will be complex and lengthy, as well as incredibly challenging for all those involved, but we will not stop until we get answers for the loved ones of those who have sadly died."

Officers, the local mayor and councillors were invited earlier to sign a book of condolence at the civic offices in Grays.

Chief Inspector Claire Talbot, district commander for Thurrock wrote: "On behalf of Essex Police we wish to offer out condolences to all those who lost their lives in such tragic circumstances.

"We also offer our thoughts to their families and loved ones whose loss is unimaginable."

Meanwhile, police announced the first 11 victims were transported by private ambulance via police escort from the Port of Tilbury to Broomfield Hospital in Chelmsford having left the port at 7.41pm.

Officers said the process of victim recovery was likely to take some time.

The next stages will be for post-mortem examinations to be carried out.

This is all being done in liaison with the coroner and the force said: "We continue to ensure the dignity of the victims is our primary consideration."

A casualty bureau for people to call if they are concerned about relatives following the incident has been set up.

It can be contacted on 0800 056 0944 for callers living in the UK, or 0207 158 0010 for callers dialling from outside the UK.

Anyone who has any information about this incident can submit information online here.

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