British police arrested a 23-year-old man from Northern Ireland on Friday as part of their enquiry into the deaths of 39 Vietnamese people found in the back of a truck near London last month.

"He was arrested on suspicion of conspiracy to traffic people and conspiracy to assist unlawful immigration and remains in custody," Essex Police said in a statement.

The man was arrested in Beaconsfield, a town 25 miles west of London, the statement said.

Identified by British police earlier this month, the 39 victims included eight females and 31 males, aged 15-44. Their bodies were found inside a lorry container on October 23. 

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The 25-year-old driver Maurice Robinson has been charged with the manslaughter of the 39 victims, as well as people trafficking, immigration and money laundering offenses.

He is expected to appear at the Old Bailey on 25 November following his first video appearance before the Chelmsford Magistrates' Court on October 28. 

A second man, Eamonn Harrison, 22, has been charged with the same offenses and British authorities are trying to extradite him from Dublin. 

Police have also been looking for two brothers from Northern Ireland.

While the investigation continues in the UK, Vietnam police arrested 10 people so far in connection with the deaths. Vietnamese authorities filed criminal charges of organizing and brokering illegal immigration and residence in foreign countries.

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Speaking on Thursday, Vietnam's Deputy Foreign Minister Bui Thanh Son said the government will provide an advance to pay for the repatriation of the bodies of victims, Vietnam's local media reported.

(With input from Reuters)