Some of the 39 people found dead in a lorry container in Grays were involved in an earlier foiled people-smuggling attempt, a court has heard.

The Vietnamese men, woman and children, aged between 15 and 44, suffocated as they were transported from Zeebrugge in Belgium to Purfleet on October 23 last year.

Jurors have heard how the victims had been sealed in the pitch black unit in temperatures of 38.5C (101.3F) for 12 hours.

Four alleged people-smugglers are on trial at the Old Bailey.

Alleged key player Gheorghe Nica 43, from Langdon Hills, and lorry driver Eamonn Harrison, 23, of Mayobridge, Co Down, Northern Ireland, who allegedly transported the migrants to the ferry at Zeebrugge, deny 39 counts of manslaughter.

Echo: The bodies were found in a lorry container in an industrial park in GraysThe bodies were found in a lorry container in an industrial park in Grays

They are accused with another lorry driver Christopher Kennedy, 24, of Co Armagh, Northern Ireland and Valentin Calota 37, of Birmingham, of being part of a wider people-smuggling operation, which Nica has admitted.

On Thursday, prosecutor Bill Emlyn Jones told the court about two earlier people-smuggling trips around October last year.

On October 11, the occupants of a farm near Purfleet allegedly witnessed 15 to 20 people get out of a lorry trailer and run towards a fleet of dark cars which then drove off at speed.

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On that occasion, the trailer was dropped off by Harrison at Zeebrugge and collected by Kennedy at Purfleet who was then met by Nica and others at the nearby pick-up point, it was claimed.

Kennedy was stopped at Coquelles in France en route to Folkestone via the Eurotunnel, the court heard.

His lorry was searched and 20 Vietnamese people were discovered in the back, Mr Emlyn Jones said.

The migrants were taken away by authorities but Kennedy was allowed to continue on his way to Kent, the court heard.

Echo: Police investigators at the scene on the day of the horrific discoveryPolice investigators at the scene on the day of the horrific discovery

Mr Emlyn Jones told jurors: “At least two of the Vietnamese nationals turfed out of the lorry that night ended up in Harrison’s lorry on October 22, and were amongst the victims who died that night.

“So you may think that this provides a powerful link between the activities of October 14, and the fatal episode on the 22nd/23rd.”

“These particular victims had secured the services of the organised criminal network to get them to the UK.

“They are providing £10,000 a head for that service.

“Obviously, they need a plan B, they try again.

“So the organisers have to arrange a replacement journey – which again involves the same teams of drivers, lorries, and so on.“

The court has previously heard that four other defendants have already admitted their part in the people-smuggling plot.

Among them are lorry driver Maurice Robinson, 26, of Craigavon in Northern Ireland, who found the 39 migrants dead in the container after picking it up in Purfleet, and hauler boss Ronan Hughes, 41, of Co Armagh, Northern Ireland, who have admitted manslaughter.