Two men and a woman have been arrested on suspicion of manslaughter and conspiracy to traffic the migrants found dead inside a refrigerated lorry

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

Police carried out search warrants in Cheshire today as part of the investigation into the bodies discovered in a lorry trailer in Waterglade Industrial Park, Grays, on Wednesday.

A man and a woman, both 38, from Warrington, have since been arrested on suspicion of conspiracy to traffic people and 39 counts of manslaughter.

A 48 year-old man from Northern Ireland was also arrested at Stansted Airport earlier today on suspicion of conspiracy to traffic people and on suspicion of manslaughter.

Meanwhile, the driver of the lorry, a 25-year-old man from Northern Ireland, remains in custody on suspicion of murder.

Three properties in County Armagh were searched in connection with the investigation yesterday.

Police were also granted a warrant for further detention.

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 taking the first convoy of bodies to the mortuary in Broomfield Hospital, Chelmsford for examination took place last night.

The first port-mortems will begin today.

A statement issued by DCC Pippa Mills: "This is a fast-moving investigation involving significant police resources dedicated to finding out the truth about what happened to the 39 people found dead in the lorry on Wednesday.

"The force will not be commenting on any speculation about the nationalities of those who have tragically lost their lives.

"I strongly urge journalists and people on social media not to speculate about the identities of those involved or the circumstances surrounding this investigation.

"We gave an initial steer on Thursday on nationality however this is now a developing picture.

"As such I will not be drawn on any further detail until formal identification processes approved by Her Majesty’s Coroner have taken place.

“I can confirm we have officers working around the clock and we have now arrested a fourth person.

"A 48 year-old man from Northern Ireland was arrested at Stansted Airport earlier today on suspicion of conspiracy to traffic people and on suspicion of manslaughter.

"It follows the arrests of a 38 year-old man and a 38 year-old woman from Warrington during warrants executed in Cheshire overnight.

"They are currently in custody also on suspicion of conspiracy to traffic people and on suspicion of manslaughter.

"A 25 year-old man arrested on Wednesday on suspicion of murder remains in custody.

"We are working closely with the National Crime Agency, the Home Office, the Foreign and Commonwealth Office, Border Force and Immigration Enforcement.

"We have begun the process of transporting the victims from the Port of Tilbury to the mortuary at Broomfield Hospital. Formal identification processes will take place as well as the examinations to establish the causes of their deaths.

"This process is likely to be a lengthy one, but it is crucial, and we’re working with Her Majesty’s Coroner to ensure the dignity of the victims and the respect for their loved ones is at the forefront of our investigation.

"The scene at the Waterglade Industrial Estate in Eastern Avenue has now been closed.

"I would like to reiterate my thanks to every person and business who has been impacted by the work we have been carrying out there since Wednesday morning.

"Finally I would like to speak directly to anyone who thinks their loved ones may have been in the trailer.

"I know you may be worried about speaking to the police. I would like to reassure you that we just want to be able to give the victims’ families answers about what has happened.

"I can’t begin to comprehend what some of you must be going through right now.

"You have my assurance that Essex Police will be working tirelessly to understand the whole picture to this absolute tragedy.

"I would also like to make an appeal to anyone living illegally in this country, who could help our investigation.

"Please come forward and speak to us without fear. I can assure you that your information will be received in strictest confidence and no criminal action will be taken against you."

Police cordons remain in place at both entrances to the industrial park last night while police conduct further enquiries.

There are reports some of the victims may be Vietnamese as three concerned families have contacted the BBC about the tragedy.

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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