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

Emergency services made the discovery at around 1.40am this morning.

Detectives at the scene of the discovery in Essex. Video: UKNIP

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

Early indications suggest 38 are adults and one is aged in their teens.

A 25-year-old man from Northern Ireland has been arrested on suspicion of murder.

It is believed the lorry came from Bulgaria and, while it was initially believed it had entered the country through Holyhead on Saturday, detectives now say it arrived in Essex earlier this morning.

They think the trailer travelled from Zeebrugge into Purfleet, and docked in the Thurrock area shortly after 12:30am this morning. The tractor unit of the lorry is believed to have originated in Northern Ireland.

The lorry and trailer left the port shortly after 1.05am.

The red and white Scania Super was this afternoon being combed by forensics officers, with several tents and screens shielding it from view. It remains cordoned off.

Chief Superintendent Andrew Mariner said: "This is a tragic incident where a large number of people have lost their lives. Our inquiries are ongoing to establish what has happened.

"We are in the process of identifying the victims, however I anticipate that this could be a lengthy process.

"We believe the lorry is from Bulgaria and entered the country at Holyhead on Saturday, October 19 and we are working closely with our partners to investigate.

"We have arrested the lorry driver in connection with the incident who remains in police custody as our enquiries continue.

Access to the industrial park has been closed.

Dartford MP Gareth Johnson said: “This is a truly shocking event. These people must have suffered unimaginable terror. Clearly there needs to be a thorough investigation in to what took place and any people smugglers who are likely to be behind this need to be identified and arrested.”

"KRAN is saddened and horrified to hear of the deaths of 39 vulnerable and exploited people..." - Razia Shariff

Prime Minister Boris Johnson said: "I’m appalled by this tragic incident in Essex. I am receiving regular updates and the Home Office will work closely with Essex Police as we establish exactly what has happened. My thoughts are with all those who lost their lives and their loved ones."

Labour leader Jeremy Corbyn added: "This is an unimaginable human tragedy of our times that happened in our country. We need to look at the whole situation to get answers."

CEO of Kent Refugee Action Network (KRAN), Razia Shariff, said: "KRAN is saddened and horrified to hear of the deaths of 39 vulnerable and exploited people.

"Unfortunately the lack of safe and legal routes for people to apply for asylum means that every day people who are simply seeking safety undertake dangerous journeys.

"In order to claim asylum in the UK you must physically be here unless you come via a resettlement programme; other than this it has become almost impossible for people to come to the UK in a safe way. That’s why people take dangerous journeys to come here.

"Our Governments need to work harder to find a solution. The sole focus on security and deterrence as a means of tackling a serious humanitarian crisis is clearly failing.

"Without legal routes to claim asylum, smugglers and traffickers will keep exploiting these vulnerable people and avoidable deaths will continue.

Essex Police Deputy Chief Constable Pippa Mills said: “At this stage we have not identified where the victims are from or their identities, and we anticipate that this could be a lengthy process.

“I would like to thank the local community and in particular those who have been directly affected by the police cordon at the industrial site.

“Thank you for your cooperation. I appreciate the impact the road closure will have on businesses within the cordon.

“I’m unable to say at this stage how long the cordon will be in place but please let me reassure you that my officers and partners will be doing everything they can to release the scene as soon as possible.

“This is an absolute tragedy and very sad day for Essex Police and the local community. We will continue to work alongside many other partner agencies to find out what led to these deaths.

“I would like to appeal for anyone who has any information to contact my officers at the Major Investigation Team on 101 or visit our website. We will update all of our channels as we are able to, but please appreciate we are in the early stages of what is likely to be a lengthy investigation.”

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.

Antony Hook, Liberal Democrat MEP for the South East, spent the summer talking with refugees and workers supporting them.

He said: “It’s very worrying and people smuggling is going on all the time, there are more and more refugees because of war, famine, water shortages and instability, just like what we’re seeing now in Syria.

“People only make desperate, dangerous journeys when they feel they’ve got no other choice, clearly what’s happened here needs to be investigated, their identities need to be established and the full story of how these people were found dead in this container needs to be established.

“The people who have done this and tried to smuggle them need to be brought to justice and feel the full arm of the law.

“In the summer I saw unaccompanied children sleeping rough in woods and rubbish tip areas, I saw women without sufficient protection, there’s no organised camps just people waiting. They’re driven because some people aren’t given places to stay, including children."

The incident will bring back tragic memories of a similar discovery 19 years ago at Dover Docks.

On June 18 2000, just before midnight, 58 dead bodies were found in a Dutch lorry in the port town. Two people were found alive but injured and taken to a hospital.

Investigations found the lorry had travelled from Zeebrugge in Belgium.

It was later determined the Chinese migrants were trapped in the container for 18 hours and likely died of asphyxiation.

The driver, from Rotterdam, was sentenced to 14 years in prison the following year for his part in a people smuggling operation coordinated by a Chinese gang.

Nine members of that gang were later jailed for their part in the tragedy.

Meanwhile, police closed a section of the M20 for nearly four hours when nine suspected migrants were found in the back of a lorry.

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