The discovery of 39 people dead in the trailer of a lorry has sparked the largest murder case in Essex Police history.

READ MORE: Essex lorry deaths: 39 found dead 'were Chinese nationals'

Here is what we know so far:

– Essex Police received reports of a number of people discovered inside a lorry container at 1.40am on Wednesday.

– The lorry was found at Waterglade Industrial Park on Eastern Avenue in Grays, Thurrock, in Essex.

– Ambulance staff found all 39 victims, including a young woman, dead inside the container.

POLICE Container(PA Graphics)

– A murder investigation was launched and the lorry driver, 25-year-old Mo Robinson, from Northern Ireland, was arrested on suspicion of murder and remains in police custody.

– Police in Northern Ireland have searched three properties near Portadown in Co Armagh in connection with the arrest.

– These include Mr Robinson’s home in Markethill, where he is understood to have moved recently, and the semi-detached family home in a development in nearby Laurelvale.

– Essex Police said all 39 victims, including eight women and 31 men, are believed to be Chinese nationals.

– The force have yet to identify the lorry victims, saying the coroner must first establish each person’s cause of death before officers move on to attempt to identify individuals.

– This will be a “substantial operation” and the force “cannot estimate how long these procedures will take”.

– The tractor unit or front section of the lorry, which police said is believed to have originated in Northern Ireland, entered the country via Holyhead, north Wales, on October 20, having travelled over from Dublin.

Police and forensic officers examine the lorry at the Waterglade Industrial Park in Grays, Essex, (Stefan Rousseau/PA)Police and forensic officers examine the lorry at the Waterglade Industrial Park in Grays, Essex (Stefan Rousseau/PA)

– The lorry trailer, where the bodies were found, travelled on a ship from Zeebrugge in Belgium to Purfleet, Essex, arriving at around 12.30am on Wednesday.

– Police believe the tractor unit and trailer left the port in Purfleet shortly after 1.05am.

– The lorry was later moved under police escort from the industrial park to a secure location at Tilbury Docks.

– The Bulgarian Ministry of Foreign Affairs said the Scania lorry was registered in Varna, a city on the east coast of the country, under the name of a company owned by an Irish citizen.

– Eric Van Duyse, a spokesman for the Belgian federal prosecutor’s office, said
that Brussels had started an investigation into the incident and that it was not yet known how long the lorry trailer spent in Belgium.

– A road haulage expert said the lorry container appeared to be a refrigerated unit, with temperatures inside able to drop as low as -25C.

– Prime Minister Boris Johnson said he was “appalled” by the incident, and said the perpetrators of the crime “should be hunted down and brought to justice”.

– Officers from the Essex Police, the National Crime Agency and Immigration Enforcement are all working on the case.

– The Police Service of Northern Ireland said it was supporting the Essex Police investigation, while the Irish police, An Garda Siochana, said they would “provide every assistance possible”.

– A casualty bureau was set up by police for people to call if they are concerned about relatives who may be involved in the incident. The number is 0800 056 0944 in the UK, and 0044 207 158 0010 internationally.

– The incident is the worst of its kind in the UK since the bodies of 58 Chinese people were found in a container at Dover, Kent, in 2000.