A man has been arrested on suspicion of murder after 39 bodies were found in the trailer of a truck in the English county of Essex.

According to Essex Police, the police were called to an industrial park by ambulance officers shortly before 2am on Wednesday morning, and arrived to find the bodies of what is currently believed to be 38 adults and one teenager — all pronounced dead at the scene by emergency services.

Police have identified the man arrested as a 25-year-old from Northern Ireland, and say the truck, originated from Bulgaria, arrived in England on October 19.

In a statement, North Essex chief superintendent Andrew Mariner said that they had begun the work of identifying the bodies. “We are in the process of identifying the victims, however I anticipate that this could be a lengthy process,” Mariner said. “We have arrested the lorry driver in connection with the incident who remains in police custody as our enquiries continue. I appreciate this cordon is going to disrupt the activity of local businesses in the area and we will work to ensure that disruption is kept as short as possible.”

In a tweet, prime minister Boris Johnson indicated that the Home Office would be providing support for the investigation.

Image: PA Wire / AAP