MO ROBINSON has pleaded guilty to 39 counts of manslaughter at the Old Bailey.
The 25-year-old had previously pleaded guilty to conspiracy to assist unlawful immigration.
The Northern Irishman was the lorry driver at the centre of the incident where 31 men and 8 women were found dead in the back of a refrigerated lorry container in Grays, Essex back in October.
The victims, who were all Vietnamese nationals, were attempting to sneak their way into the UK after being transported across the English Channel from Belgium on October 23 last year.
Among the victims, 10 were believed to be teenagers, while one was as young as 15-years-old.
Robinson admitted his guilty plea via video-link, with most lawyers and reporters attending via Skype, due to social distancing restrictions.
He was allegedly part of a network of conspirators who were looking to smuggle migrants into the UK
Last month, it was determined that the 39 victims died from asphyxia and hyperthermia.
When the container was opened, blood was found on the inside of the doors.
The family of one of the victims also received heartbreaking text messages on the day of the tragedy, explaining how the group were running out of air and were not going to make it.
British Romanian Gheorghe Nica, 43, who lives in Essex, denied 39 counts of manslaughter, as well as one count of conspiracy to commit unlawful immigration.
Romanian national Alexandru-Ovidiu Hanga, 27, who also lives in Essex, denied a charge of conspiracy to commit unlawful immigration.
Christopher Kennedy, 23, of Darkley in Co. Armagh, has previously denied the same charge.
Prosecutor William Emlyn Jones QC has asked for three weeks to decide whether to proceed with a trial against Robinson on the outstanding charges he faces.
The other defendants face a trial at the Old Bailey lasting up to eight weeks from October 5.