A woman called police three times about people jumping out of a lorry less than two weeks before the deaths of 39 migrants, a court has heard.
Four men are on trial at the Old Bailey in connection with the deaths of the 39 Vietnamese nationals.
They suffocated in a lorry trailer as they were transported from Zeebrugge in Belgium to Purfleet on 23 October 2019.
Marie Andrews said she saw about 15 migrants outside her mobile home in Orsett, Essex, on 11 October last year.
Prosecutors claim it was one of two “successful” people-smuggling runs before the 39 deaths.
Giving evidence, Ms Andrews said she dialled 999 on 11 October after her partner Stewart Cox left for work and found a lorry and four cars in their lane.
She told the operator “a load of immigrants just got out of a lorry into Mercs”.
Ms Andrews said: “I saw some legs come out. It was a shock, like anybody would be shocked to see this, particularly down a lane people would not know.”
She went on to call the non-emergency number 101 twice, the court heard.
Jurors previously heard from Mr Cox who said he had seen 10 to 20 people “with rucksacks” run from a lorry towards four cars.
Gheorghe Nica, 43, of Basildon, Essex, and lorry driver Eamonn Harrison, 23, deny the manslaughters of 39 Vietnamese people, aged between 15 and 44.
Mr Harrison, of Mayobridge, County Down, Christopher Kennedy, 24, of County Armagh, and Valentin Calota, 37, of Birmingham, deny being part of a people-smuggling conspiracy, which Mr Nica has admitted.
Jurors have been told four others have admitted a role in the people-smuggling ring.
The trial continues.