TEHRAN, Young Journalists Club(YJC)_The truck, which is said to have entered Britain via the Welsh port of Holyhead on Saturday, was found by ambulance workers at Waterglade Industrial Park, Grays.
"This is a tragic incident where a large number of people have lost their lives. Our enquiries are ongoing to establish what has happened," Essex Police Chief Superintendent Andrew Mariner said.
"We are in the process of identifying the victims, however I anticipate that this could be a lengthy process."
A 25-year-old-man from Northern Ireland has been arrested on suspicion of murder. He remains in custody.
A cordon has been put in place and access to and from the industrial park remains closed.
"We are working with Thurrock Council to mitigate against any impact our investigation scene will have locally." Mariner said.
British Prime Minister Boris Johnson said he was appalled after 39 bodies were found in a container east of London.
“I’m appalled by this tragic incident in Essex,” Johnson said in a tweet.
“I am receiving regular updates from the Home Office and will work closely with Essex Police as we establish exactly what has happened,” he said.
“My thoughts are with all those who lost their lives & their loved ones.”
Britain’s interior minister Priti Patel said she was “shocked and saddened” by the news.
“Shocked & saddened by this utterly tragic incident,” Patel said on Twitter. “Essex Police has arrested an individual and we must give them the space to conduct their investigations.”